14:30 Hello everyone and welcome to AUTOSPORT Live for the penultimate round of the FIA Formula 1 World Championship - the Petrobras Brazilian Grand Prix.

The Jose Carlos Pace circuit at Interlagos has thrown almost everything at the teams and drivers this weekend. Three of the four track sessions have been disrupted, and there is likely to be yet more fun this afternoon as the drivers battle it out at the scene of Lewis Hamilton's dramatic championship victory last year.

The race itself starts at 16:00 GMT, but before then we will review Saturday's action at the circuit in case you missed it, take a look at the three championship protagonists, as well as looking at the weather forecast. We'll also analyse the fuel weights and what they may mean for the first stint of the race.

14:35 The clouds parted earlier this morning and Sao Paulo has enjoyed the sunshine for the first time in several days.

Throughout the morning and early afternoon some cloud has built up, with a chance of showers during the race still keeping the teams glued to their radar screens.

The maximum air temperature this afternoon is higher than at any point during the weekend at 24 degrees Celsius.

14:40 A quick development of heavy, thundery showers on Saturday made track conditions impossible at times, throwing plans for the final practice session into chaos.

The circuit was awash just minutes before the session was scheduled to begin, prompting race control to delay proceedings as the medical helicopter could not fly. The first couple of storms would soon pass, allowing the cars out for a shortened 18-minute run ahead of qualifying.

Kimi Raikkonen and Fernando Alonso were involved in harmless incidents, but Romain Grosjean was less fortunate. The Frenchman aquaplaned on a large area of standing water exiting Turn 5 and skated off the road, launching over the bumpy grass and into the barrier.

Nico Rosberg topped the mini-session for Williams, with team-mate Kazuki Nakajima following him home in second spot.

Rosberg tops shortened practice three

14:45 Shortly before qualifying it was a case of deja-vu as the heavens opened once again, although the knock-out session got underway on time.

The first phase was soon red-flagged when Giancarlo Fisichella spun in the Senna S and accidentally pressed the engine kill button while trying to control the slide. The Italian was stranded sideways on the racing line - instant elimination.

The rain fell heavier and the race director held back the restart for time until conditions were better. First qualifying was then completed but with some big shocks. Neither McLaren driver could make it into the top 15 and joining them was Sebastian Vettel after a disastrous run in the Red Bull.

Phase two was started after a further delay for weather. But in less than three minutes the red flags were out yet again - this time for Tonio Liuzzi after the Italian aquaplaned on the start-finish straight. He was pitched to the left into the pitwall and then careered towards the outside retaining wall at Turn 1. Liuzzi was unhurt but his Force India was badly damaged.

70 minutes later qualifying two was resumed to a conclusion with another shock in store. Jenson Button stayed out on the drying circuit with full wet tyres when conditions began to favour intermediate rubber. He starts 14th.

Rubens Barrichello was therefore the only championship challenger to make it through to the shootout, and the Brazilian made it count, surging his way through the spray to claim pole position with a last-gasp 1m19.576s lap.

Mark Webber starts alongside the Brawn driver on the front row of the grid, with Adrian Sutil a fine third, Jarno Trulli fourth, Kimi Raikkonen fifth and Sebastien Buemi a career-best sixth in the Toro Rosso.

Barrichello on pole, Button down in 14th

14:50 Several hours after qualifying was completed, it was announced that Force India would be changing the gearbox on Tonio Liuzzi's car after that heavy shunt at Turn 1.

The Italian drops five places on the grid for today's race and will start from the back, in 20th position.

14:52 The drivers' parade has just ended, with the competitors getting a warm reception from the massive crowd as they toured the circuit on a flat-bed truck.

The crowd's vocal support was clearly in favour of title contender Rubens Barrichello, who starts from pole this afternoon.

14:55 Motor racing enthusiasts love to debate and discuss the action on track, and the live forum at the bottom of the screen is your chance to let everyone know your thoughts on events as they unfold at the circuit.

• Can Rubens Barrichello win today's 71-lap race and heap more pressure on Brawn team-mate Jenson Button?

• What can Sebastian Vettel do from 15th on the grid? He really needs to make the podium to have any chance in the title battle.

• The theme of the weekend has of course been the weather. Have you had enough of the rain this weekend?

Tell the world what you think.

Click the SHOW LIVE FORUM link in the red bar at the bottom of your browser window if you'd like to join the debate.

14:58 The following shows the weight of each car, fuelled for the first stint of today's grand prix:

Pos  Driver                             Weight (kg)
 1.  Barrichello  Brawn-Mercedes        650.5                  
 2.  Webber       Red Bull-Renault      656.0                  
 3.  Sutil        Force India-Mercedes  656.5                  
 4.  Trulli       Toyota                658.5                  
 5.  Raikkonen    Ferrari               651.5                  
 6.  Buemi        Toro Rosso-Ferrari    659.0                  
 7.  Rosberg      Williams-Toyota       657.0                  
 8.  Kubica       BMW-Sauber            656.0                  
 9.  Nakajima     Williams-Toyota       664.0                  
10.  Alonso       Renault               652.0                  
11.  Kobayashi    Toyota                671.5       
12.  Alguersuari  Toro Rosso-Ferrari    671.5          
13.  Grosjean     Renault               677.2       
14.  Button       Brawn-Mercedes        672.0      
15.  Vettel       Red Bull-Renault      683.5          
16.  Kovalainen   McLaren-Mercedes      656.5            
17.  Hamilton     McLaren-Mercedes      661.0            
18.  Heidfeld     BMW-Sauber            650.5      
19.  Fisichella   Ferrari               683.5
20.  Liuzzi       Force India-Mercedes  680.0 *

* Five-place grid penalty for gearbox change

15:00 Rubens Barrichello delighted the home crowd with pole on Saturday and looks to be in a straight fight with Mark Webber for the win this afternoon.

Webber is well-placed to deny the Brazilian an emotional home win as he lines up on the front row with a couple of laps more fuel than Barrichello. The Australian has looked on top form all weekend and is certainly in with a good chance of taking his second win.

The front row men will hope rain holds off as sporadic showers are likely to cause chaos and favour heavier cars from behind.

The fuel loads are quite similar across the top eight. Stuil again qualified brilliantly in the Force India, which remains extremely quick on straight line speed. It was also a great effort from Buemi in the Toro Rosso, who will be looking for a points finish in the improving STR5.

The danger man in this area of the grid is clearly Kimi Raikkonen in the KERS-shod Ferrari, giving the Finn an assisted launch off the start, helping challenge those ahead, and a boost up the hill from Juncao to line up overtaking moves into the first corner.

Kazuki Nakajima has a good chance of his first points of the year from ninth, with his additional fuel load carrying him several laps further than his rivals, and a little more flexibility in case of a shower.

15:05 Outside the top ten is a mouthwatering mix of strategies. Kobayashi, Alguersuari and Grosjean will certainly have to look out for challenges from behind as several expected front-runners look to recover from disastrous qualifying performances. Such a mix-up of the grid could certainly lead to some great racing this afternoon.

Jenson Button lines up 14th and has a lot to do to even score points today. He will be hoping to clear the heavier Grosjean in the early stages and needs to quickly work up the order to prevent Barrichello taking a major chunk out of his points lead. The title leader is of course in a dangerous part of the grid, heading into an opening complex of corners where first-lap collisions are frequent.

Sebastian Vettel has opted for a heavy strategy, presumably in the hope of rain. The Red Bull has been quick here in the dry but the young German needs a remarkable race to stay in title contention.

The McLaren pair of Kovalainen and Hamilton will be fascinating to watch, with both opting for a lighter strategy in an attempt to make early progress. KERS should help them line up overtaking moves along the main straight, although the system is difficult to fully charge during the race.

15:10 Conditions are beginning to change in the skies above Interlagos.

The early morning sunshine is disappearing as clouds build up in the Sao Paulo region.

Showers are expected later, but it is too close to call whether the rain will fall before the end of the race.

15:15 The pitlane will open in 15 minutes' time, allowing the drivers to bring their cars onto the track for the first time today.

With so much rain over the past couple of days, they will be confronted with a racing surface that has absolutely no Formula 1 rubber laid down on it.

On Friday afternoon we saw that rear tyres were graining up quite badly during practice on some cars. A similar situation is likely for the early laps of the race, creating a headache for the race engineers, although the slight increase in temperature today will be welcome news.

15:20 Both championships could be decided this afternoon, but the one that is most likely is the constructors' title race, in favour of Brawn GP. The Brackley-based team have scored a massive 156 points and with two races to go, have a 36.5 point lead over Red Bull.

With 36 points on offer for a pair of one-two finishes, team boss Ross Brawn knows that his two drivers only need to score one point for eighth place between them to secure the title - even if Sebastian Vettel and Mark Webber somehow finish first and second.

15:25 Jenson Button holds the advantage in the drivers' title race heading into this afternoon's grand prix and is the only man who can be crowned champion today.

Rubens Barrichello needs to score five points more than his team-mate to force a showdown in Abu Dhabi and yesterday's qualifying result has certainly given the home hero every chance. Even if Button doesn't recover into the points, Barrichello needs to finish in the top four.

Sebastian Vettel's championship hopes took a major blow in qualifying yesterday as the Red Bull driver really needs to win to keep his title hopes alive. Second would be enough, if Button fails to score, but the young German will need a spectacular performance today to remain in the hunt from 15th on the grid.

Clearly, if Barrichello and Vettel fail to finish the race today, Button is automatically champion.

15:30 The pitlane is now open for the drivers to make their way around to the grid.

15:30 Heikki Kovalainen is the first man out of this pits with super-soft tyres on his McLaren.

15:31 Rubens Barrichello practices a start at the pit exit and heads onto his lap to the grid.

15:32 The crowd at Descida do Lago go wild for Barrichello as he continues his lap of the circuit.

15:33 Replays show that something fell off Vettel's Red Bull as he braked at Juncao on his out lap to the grid.

15:34 Vettel has pitted the Red Bull and the team are looking over the car to see what that problem was.

15:34 Rubens Barrichello brings his Brawn to the pole position starting slot. The crowd cheers him to the rafters as he climbs out of the car.

15:36 Jenson Button joins the grid line-up on the grid in his Brawn.

15:36 The sky is clouding over above the circuit and conditions are beginning to turn overcast.

15:37 There are still one or two small patches of blue sky around, but these are rapidly disappearing.

"I think that we have a great car in these conditions. If it rains we need to get it right. We are expecting some of that for the end of the race, but it could happen (rain)."
Rubens Barrichello, polesitter speaking to BBC TV

15:41 Although there is no imminent threat of rain, the teams are prepared with wet tyres on the grid. A heavy shower struck the grid last year.

15:43 The sun briefly comes out again as the clouds continue to build over the circuit. It will be several minutes yet before the patches of blue sky completely disappear.

15:43 Hasty repairs are taking place around the radiator of Vettel's car where that part was ejected on his lap to the grid.

15:46 The Brazilian national anthem rings out over the Interlagos public address system. Will the Paulistas be hearing it again in celebration of a Barrichello win?

15:49 The track temperature is 31 Celsius as the sun again breaks through the clouds. The ambient is a warm 27 degrees.

15:52 The atmosphere is incredible on the grid with the vocal fans so close to the line up of cars.

15:55 The formation lap is just five minutes away. Barrichello needs to get the jump to ensure a good early stint, while Vettel and Button must stay out of trouble.

15:56 The safety car roars around the circuit, preparing for the start.

15:57 Sebastian Vettel and Jenson Button will pull up to their grid slots and face a nightmare right in front of them.

Inexperienced racers Kamui Kobayashi, Jaime Alguersuari and Romain Grosjean are all directly ahead of the two title contenders.

15:59 The engines begin to fire with a minute to go before the formation lap.

15:59 The harder tryres are the choice of front row men Barrichello and Webber.

16:00 The formation lap begins at Interlagos. All 20 drivers leave the grid without problem.

16:00 The harder tyre is a popular choice as there is a risk of trouble with the soft rubber due to the lack of grip after recent rain.

16:01 Rubens Barrichello immediately starts weaving from side to side to generate some heat in the medium compound tyre.

16:01 Kimi Raikkonen is gambling on the softer tyre to help his KERS-assisted launch.

16:02 Barrichello leads the pack through the twisty infield section as the formation lap continues in front of an enthusiastic crowd.

16:02 Barrichello winds up the pace and brings the field down towards the grid.

16:02 Vettel is warned about his engine temperatures. He certainly had some radiator dramas in the lead up to the race.

16:03 The front couple of rows are now in position. The field is forming up neatly behind Rubens Barrichello.

Stand by for action ...

Lap 1: The five red lights go out and we are racing in Brazil!

Lap 1: Barrichello gets a good start and leads from Webber into the Senna S as Raikkonen tries to muscle into contention!

Lap 1: Through the twisting middle part of the lap it is Barrichello from Webber and Raikkonen with a damaged front wing.

Lap 1: Heavy contact on the first lap between Adrian Sutil and Jarno Trulli but up front it is all happening.

Lap 1: There is lots of carngae as Raikkonen slows through the pack.

Lap 1: The safety car has been deployed.

Lap 1: Jarno Trulli is very upset with Adrian Sutil.

Lap 2: Raikkonen pits for a replacement nose.

Lap 2: Jarno Trulli has stormed over to Adrian Sutil and is raging with the German. We await a replay to see what happened between the pair.

Lap 2: Kovalainen pits at the end of lap 1 ... and leaves the box with the fuel hose still attached to the car!

Lap 2: Barrichello leads behind the safety car from Webber, Rosberg, Kubica and Buemi.

Lap 3: Some fuel sprays out of the hose as Kovalainen travels down the pitlane. The droplets catch fire in the pitlane but eventually the problem is sorted out.

Lap 3: Replays show Raikkonen lost his front wing in contact with Mark Webber on the run down to Turn 4.

Lap 3: The mechanics take off the fuel hose and Kovalainen is able to rejoin the race.

Lap 3: Jenson Button is up to ninth with all this chaos.

Lap 3: Replays show that Adrian Sutil was boxed in behind a slowing Kimi Raikkonen as the Finn slowed with his damaged front wing. Trulli tried to fight round the outside of Sutil exiting Turn 5 but failed, lost control and crashed into the side of the Force India.

Lap 4: Button is behind the heavier Grosjean but has made good progress through all those incidents.

Lap 4: Both Trulli and Sutil then speared off the road. Fernando Alonso was also involved in the incident and is also out of the race.

Lap 5: Replays of the start show that Heikki Kovalainen was tipped lightly into a spin by none other than Sebastian Vettel. Kovalainen rejoined, came into the pits and then had that fuel hose problem. He is 16th.

Lap 5: Lewis Hamilton made a stop in that scramble and has changed onto the harder tyre for a one-stop strategy.

Lap 5: The safety car will come in at the end of this lap.

Lap 6: The safety car comes into the pitlane and we are racing once again.

Lap 6: Vettel did not pit after that light contact with Kovalainen at the start and his car looks to be okay so far. He is 11th.

Lap 6: Robert Kubica challenges Rosberg into Turn 1 and the Pole is through for third.

Lap 6: Jenson Button has a great run at Romain Grosjean and it's a wonderful move by the Briton. Good attacking driving.

Lap 7: Button is now up to a sensational eighth place having taken good advantage from the chaos on the first lap.

Lap 7: Button is charging after Kazuki Nakajima and he's nailed the Williams driver at Turn 1! Button now seventh.

Lap 7: Barrichello sets the fastest lap as he leads by a second while behind team-mate Button surges forward.

Lap 8: Romain Grosjean has had a problem following the Button pass and has lost several places. He is now 12th.

Lap 8: Webber is still second from Kubica, Rosberg, Buemi, Kobayashi and Button.

Lap 8: Button is already on the case of Kobayashi and is busy challenging the Toyota.

Lap 9: Button is already seventh and in the points after a very strong start from the world championship leader.

Lap 9: Barrichello sets the fastest lap at 1m14.454s as he stretches to 1.7s in the lead over Webber.

Lap 9: Sebastian Vettel tries to pass Kazuki Nakajima for eighth place but the Japanese holds his line and runs Seb onto the grass on the run to the Ferrardura. Contact avoided and they continue in eighth and ninth.

Lap 10: Robert Kubica is closing in on Webber's Red Bull with the BMW working well in this early phase.

Lap 10: Button again dives to the inside of Kobayashi but the Japanese is defending well on his debut.

Lap 10: Behind Button's charging drive, Nakajima is eighth and has Vettel and Heidfeld tight up behind him.

Lap 11: Heikki Kovalainen passes Romain Grosjean for 13th position. Lewis Hamilton is further up the order in 11th and fueled heavily.

Lap 11: Mark Webber sets the fastest lap, pegging the gap at 1.8 seconds. He needs to stay in touch with the lead Brawn before running longer at the first stop.

Lap 12: Kobayashi continues to frustrate Button's efforts as the pair continue to battle over sixth.

Lap 12: Kimi Raikkonen is stuck down the field following that front wing change at the end of lap 1. He is 14th and not making any headway.

Lap 13: Kazuki Nakajima in eighth is now hanging on to Button and Vettel is just over one second behind him.

Lap 13: Barrichello leads by 1.8 seconds from Webber and Kubica. Rosberg is fourth, with Buemi slipping away in fifth.

Lap 14: Kobayashi continues to hold off Button, who has slipped away slightly from the back of the Toyota in the last couple of laps.

Lap 14: Nick Heidfeld is 10th, running close behind Vettel. Lewis Hamilton is just a second behind in 11th, with team-mate Kovalainen in 12th.

Lap 15: Laptimes are fading for many drivers as their tyres take serious punishment on this 'green' track surface.

Lap 15: Romain Grosjean is now dropping back in 13th and about to come under attack from Raikkonen. Alguersuari is 15th with Fisichella and Liuzzi bringing up the rear.

Lap 16: Webber continues to keep Barrichello within two seconds, which is enough for the Australian to pounce with his fuel load at the first stops.

Lap 16: Heikki Kovalainen is under investigation by the stewards following that scary pitstop at the end of lap 1 when he took the fuel hose for a walk.

Lap 17: Barrichello again sets the fastest lap but Webber is only a fraction slower. Robert Kubica continues to lap strongly, just a second behind.

Lap 17: Sebastian Vettel is dropping away by one-tenth of a second per lap from Nakajima. Heidfeld in 10th and Hamilton 11th are on his tail.

Lap 18: There is a large dark cloud just beginning to float over the circuit. Beyond it the skies are still reasonably bright at the moment.

Lap 18: Button continues to be held back by Kobayashi and has now fallen over 17 seconds back from his team-mate's lead.

Lap 18: The first lap incident between Adrian Sutil and Jarno Trulli will be investigated after the race.

Lap 20: Barrichello has edged out the lead to 2.5 seconds as Webber comes under some pressure from Kubica.

Lap 20: Lewis Hamilton could be sitting in a very good position here. He's 11th at the moment but fueled for many laps and has more flexibility with his strategy than some of the others if it rains.

Lap 21: Barrichello sets the fastest lap again, extending the lead to 2.7 seconds. This is putting Rubens in with a good chance of keeping the lead.

Lap 22: Rubens Barrichello pits from the lead.

Lap 22: Nick Heidfeld comes into the pits from 10th place. He's out again after 7.8 seconds.

Lap 22: Webber must now push as Rubens heads out with fuel and the harder tyres.

Lap 22: Lewis Hamilton is now promoted to that 10th place and can have a crack at Sebastian Vettel. That could be interesting.

Lap 22: Barrichello resumes in traffic, behind Nakajima.

Lap 23: This is good news for Webber, who is pressing on with the remainder of his fuel load.

Lap 23: Vettel seizes the chance to put some manners on Barrichello at Turn 6 and the move sticks! Vettel up to eighth as Barrichello right behind him in ninth.

Lap 24: Robert Kubica pits his BMW from thrid.

Lap 24: Barrichello is not immediately quick on this second stint and Hamilton tries to come through past the Brawn like Vettel did. Close racing between these two for ninth.

Lap 24: Replays show Button had made a move on Kobayashi but couldn't slow the Brawn enough and remains behind.

Lap 24: Robert Kubica resumes ahead of Barrichello!

Lap 25: This is a disaster for Rubens, with traffic costing him track position as the others make later stops.

Lap 25: Rosberg and Buemi make their stops.

Lap 25: Barrichello is still stuck down behind Vettel. Hamilton and Kovalainen are climbing all over him!

Lap 25: Jenson Button is through! The championship leader finally makes a move stick on the Toyota and he needs to push now.

Lap 26: Meanwhile, Webber sets the fastest lap and will surely end up ahead of Kubica and Barrichello as he stops.

Lap 27: Kamui Kobayashi sends an amazing move on Kazuki Nakajima to take third place at the Senna S before they come into the pits for their first stop.

Lap 27: Webber has a clean stop and surges out of the pits. He is ahead of Button and rivals Kubica and Barrichello.

Lap 27: Nakajima has pitted at the end of that lap dropping down the order and out of the points.

Lap 28: Button is currently second but is yet to stop.

Lap 28: Nico Rosberg is slowing! The Wiliams driver is touring back to the pits after such a strong first stint.

Lap 28: Kobayashi is now third after an exceptionally strong drive so far, from Vettel fourth.

Lap 29: Rosberg pits with smoke coming from the back of the FW31. Race over and he pulls into the garage.

Lap 29: Webber is clear off into the lead after leaping both Kubica and Barrichello at the stops. The traffic for the latter was a disaster, denting his title hopes.

Lap 30: It's a double blow for Williams. Kazuki Nakajima dropped right down the field to 15th and effectively last position following his pitstop.

Lap 30: Button makes his first stop from second on the road.

Lap 30: The top eight in the race are covered by just 13 seconds as this amazing race continues.

Lap 30: The title leader takes more hard tyres and feeds out into heavy traffic between the Toro Rosso pair.

Lap 31: Heikki Kovalainen pits from eighth position in the McLaren and rejoins at the rear of the field, behind Nakajima.

Lap 31: Button has rejoined in 12th place and is currently in a Toro Rosso sandwich.

Lap 31: Kobayashi makes his first stop after a strong first stint.

Lap 32: But it's not a sandwich for long as Alguersuari pits for the first time this afternoon. He rejoins towards the rear of the field.

Lap 32: Barrichello and Hamilton are scrapping over current fourth place. The McLaren driver is moving up well on his one stop strategy with the aid of KERS.

Lap 33: Kazuki Nakajima has crashed at the end of the back straight. He is okay after heavy contact with the Curva de Lago tyre barriers.

Lap 33: Webber leads by 6.8 seconds from team-mate Vettel, who has yet to make his one stop.

Lap 34: Hamilton was again ready to challenge Barrichello into Turn 4 but the yellow flags are only now bieng cleared from the Nakajima incident.

Lap 34: Replays show that Nakajima's exit was the result of round two in the all-Japanese fight. Kobayashi pitted and resumed onto the track.

Nakajima was closing fast on the accelerating Toyota and tried to go both sides to pass the TF109. Kobayashi then weaved to keep his compatriot behind and they made contact, sending Nakajima off the track at high speed.

Lap 35: Kamui Kobayashi's Toyota appears to be undamaged following that incident and he runs 12th.

Lap 35: Jenson Button has passed Sebastien Buemi for eighth position entering the Senna S. Buemi ran him close but Jenson squeezed through and now is set for a point.

Lap 36: Hamilton is again pressuring Barrichello while the Brawn is heavy and the McLaren is light. Both have one more stop to make.

Lap 37: Romain Grosjean pits from ninth and has rejoined down in 13th.

Lap 37: A light Vettel continues to catch team-mate Webber as the Red Bulls run one-two. He is the fastest man on track as we approach half distance

Lap 37: Vettel is due for a stop shortly but will need to swap to the softer tyres for a lengthy stint to the finish.

Lap 37: Vettel indeed stops on this lap.

Lap 38: Vettel takes the harder tyres so plans a short final run on soft rubber.

Lap 38: Vettel resumes just behind Button after a slight fumble on the left-front wheel.

Lap 39: Giancarlo Fisichella pits for the first and only time from ninth position. he rejoins in 13th place, just ahead of Jaime Alguersuari.

Lap 39: Webber leads by 6.6 seconds over Robert Kubica. Barrichello is third, with Lewis Hamilton right behind him.

Lap 40: Kimi Raikkonen is fifth, with Button up to a hard-fought sixth, ahead of Vettel.

Lap 41: Hamilton is right with Barrichello again and looking for a move on the Brawn.

Lap 42: At the back end of the points, Sebastien Buemi is eighth and has a comfortable 6.4s buffer over Tonio Liuzzi. Kobayashi is 10th.

Lap 42: Hamilton will have to pit earlier and for longer than Barrichello, but does not have to run the super-soft tyre after discarding them early.

Lap 42: Heikki Kovalainen is 11th with Grosjean 12th. Fisichella is 13th but coming under increasing pressure from Jaime Alguersuari who is the final runner in 14th.

Lap 43: Hamilton makes his final stop.

Lap 43: There is no problem fuelling Hamilton with the sole-remaining fuel hose but he has a major moment on the pit exit road.

Lap 44: Raikkonen is in for his final stop, taking super-soft rubber to the finish.

Lap 44: Hamilton rejoins from his pitstop in ninth position, just behind Tonio Liuzzi.

Lap 45: Webber continues to lead but Kubica has closed to 5.5 seconds behind.

Lap 46: Liuzzi pits from eighth place in the Force India and can run to the finish, but is near the rear of the field.

Lap 46: There maybe sunshine over the circuit right now, but beyond the circuit the clouds are building up very quickly once again. Rain still cannot be ruled out before the end of the race.

Lap 46: Barrichello is still third, with Button fourth and being told to push hard to counter the threat of Hamilton.

Lap 47: Kubica pits for his fuel and soft rubber to the flag.

Lap 48: At the back of the field there is a tremendous fight for 12th place. Fisichella is holding it at the moment, but Alguersuari and Liuzzi are all tight up behind him.

Lap 48: Barrichello is promoted to second by Kubica's stop but he has little chance of beating the Pole or leader Webber, unless rain intervenes.

Lap 49: Vettel continues to hound Button over fourth on the road.

Lap 49: A battle is slowly developing for the final point. Kamui Kobayashi is eighth at the moment, but Heikki Kovalainen has been slowly catching him for the last couple of laps.

Lap 50: Lewis Hamilton remains seventh but is set to leap forward as the others make final stops.

Lap 50: Barrichello makes his final stop.

Lap 51: The sky continues to darken above the circuit as that enormous black cloud ever so slowly drifts closer to the final portion of the lap.

Lap 52: It is a clean pit visit for Barrichello but he needs more points than he looks set for at the moment.

Lap 52: Jaime Alguersuari pits from 14th. He therefore loses touch with Tonio Liuzzi.

Lap 52: Hamilton is again just behind Barrichello on the road and will be fighting the Brawn for position.

Lap 52: Heikki Kovalainen is now less than one second behind Kamui Kobayashi as that fight for eighth brews up.

Lap 52: Mark Webber pits from the lead.

Lap 53: The Australian takes his tyres and fuel, resuming clear in the lead and on course for victory in Brazil.

Lap 54: Kubica is behind Webber on the road in second with all his stops completed.

Lap 54: The crucial group is Button, Vettel and Buemi, yet to stop, and looking set to come out behind Barrichello and Hamilton.

Lap 55: Buemi pits for his fuel to the finish.

Lap 55: Down the field, Kobayashi is promoted to seventh with Buemi's stop. Kovalainen is still close behind the Toyota but Kimi Raikkonen in ninth is catching both of them.

Lap 55: The Brawn crew are ready for Button, who pits.

Lap 56: It is a perfect stop for Button and he feeds out in a scrap with Kovalainen.

Lap 57: Vettel makes his final stop without incident.

Lap 57: Vettel has jumped past Button, who is losing time behind Kovalainen.

Lap 57: Grosjean pits for the final time and rejoins in 13th place.

Lap 57: Vettel is now fifth, with Button seventh but still on course for the title.

Lap 58: Mark Webber leads from Kubica, Barrichello, Hamilton, Vettel, Kovalainen and Button.

Lap 58: Kimi Raikkonen in eighth is closing down the 3.7s gap to Button as the Briton remains trapped behind Heikki Kovalainen.

Lap 59: Button will still take the title if it stays like this.

Lap 60: Kovalainen pits, releasing Button up to a secure sixth.

Lap 60: Sebastien Buemi is ninth and also closing down on Raikkonen but they are both promoted with Kovalainen's final pitstop.

Lap 61: Vettel is again the fastest man on the track as he catches both Hamilton and Barrichello for the final podium place.

Lap 61: Barrichello reports vibration from his right front tyres as Hamilton sends a move up the inside of the Brawn.

Lap 62: A battle is on for 10th place between Fisichella and Kobayashi. The Toyota is all over the back of the Ferrari and looks set to make a move soon.

Lap 62: The McLaren is through for the final podium place and Barrichello's title challenge continues to fade.

Lap 62: Rubens must not fall any further down the order or his title race will end, even if Button drops out of the points.

Lap 63: As it stands, Button is well-placed for the title after a very determined drive this afternoon.

Lap 63: Kobayashi is all over the back of Fisichella now as their fight for 10th place continues.

Lap 63: Barrichello is told his vibration is a puncture!

Lap 64: This is the end of the road for Barrichello as he is forced into the pits for tyres.

Lap 64: Button is now virtually assured of the title as Barrichello resumes down in eighth.

Lap 65: Barrichello's right rear tyre was punctured, possibly after contact with Hamilton's McLaren.

Lap 65: Barrichello has rejoined in eighth place and is set to score just a single point this afternoon when he really needed all 10 for victory.

Lap 66: Webber continues to lead and is under no threat from Kubica behind.

Lap 66: Behind Barrichello, Kovalainen is ninth with Fisichella 10th, Kobayashi 11th, Liuzzi 12th, Grosjean 13th and Alguersuari 14th.

Lap 67: Hamilton holds the final podium place, which is vital points in McLaren's battle with Ferrari in the constructors' title.

Lap 68: Button is warned of possible rain drops in the remaining laps as the skies are threatening around the circuit.

Lap 68: Kobayashi is still hounding Fisichella as they battle for 10th spot ... and he sends a good move up the inside of the Ferrari at Turn 1.

Lap 68: Kobayashi takes over 10th place with Fisichella now 11th.

Lap 69: Mark Webber looks set for victory at Interlagos. The Australian has 8.4s over Robert Kubica. with Hamilton third.

Lap 70: Vettel is fourth and doing all he can to close down on the McLaren, but time is against him.

Lap 70: Jenson Button is fifth and is about to cross the line as Mark Webber starts the last lap of the race.

Lap 70: Button starts his last lap and is now less than three miles from the title.

Lap 71: Mark Webber has just a few corners to go to claim his second victory of the season.

Lap 71: Mark Webber wins in Brazil!

The Red Bull driver put in the pace when it mattered, leaping past Barrichello at the first stops and was then never challenged to the flag.

17:35 Robert Kubica takes a strong second for BMW with a stellar drive for his best result of the season.

17:35 Lewis Hamilton takes third after a brilliant drive from the back of the field, with a clever strategy change from the team paying off amid the first-lap chaos.

17:36 Jenson Button is the 2009 Formula 1 world champion!

17:36 Vettel takes fourth for Red Bull after doing all he could from a lowly grid spot.

17:36 But it is fifth for Jenson Button and that is all he needs after a dogged drive with some vital overtaking moves.

17:37 There is jubilation in the Brawn garage as they celebrate both world championships.

17:37 Button is absolutely delighted as he sings 'We are the champions' over the radio.

17:37 Kimi Raikkonen finished sixth for Ferrari with Buemi scoring two points in seventh and Barrichello eighth in the end.

17:38 Button punches the air as he begins to reflect on securing his first world championship.

17:39 Mark Webber heads into parc ferme as the delighted winner of the grand prix.

17:39 Heikki Kovalainen was ninth, out of the points. Kamui Kobayashi was 10th on his debut, with Fisichella 11th, Liuzzi 12th, Grosjean 13th and Alguersuari 14th and the last classified finisher.

17:39 Button makes it back to the pits and jumps out of his Brawn. He is immediately congratulated by team-mate Barrichello.

17:40 The world champion runs down the pit lane and is mobbed by photographers.

17:41 Six drivers retired from the Brazilian Grand Prix:

Kazuki Nakajima was taken out of contention by Kamui Kobayashi - a move that will cause ructions in Japan.

Nico Rosberg trailed into the garage with smoke out the back of the car after a strong start to the race.

Nick Heidfeld amazingly ran out of fuel just before his pitstop.

Adrian Sutil, Jarno Trulli and Fernando Alonso were all involved in a big incident on the first lap as the pack sorted itself out.

17:41 Button continues to celebrate wildly, helmet on, embracing everyone he can find.

17:43 The three podium drivers step out onto the podium as 'Advance Australia Fayre' rings out over Interlagos following a great drive by the Red Bull pilot.

17:43 The Austrian national anthem now plays for today's winning constructor, Red Bull Racing.

17:44 Webber takes the unique prize for victory in Brazil. He is delighted with his second career win.

17:44 Race engineer Ciaron Pilbeam gets the constructors' trophy.

17:45 Robert Kubica takes his award for second place today. It was a gritty drive but Webber was always in control of the gap.

17:45 Lewis Hamilton holds aloft his prize after a great drive to third.

17:45 The champagne sprays on the podium at the end of a tense Brazilian Grand Prix.

17:46 Jenson Button is embraced by Bernie Ecclestone as he prepares to talk with the media scrum.

17:47 Webber, Kubica and Hamilton vacate the podium but the interest is clearly elsewhere at the moment, as Jenson Button and the Brawn team take in their first few minutes as champions of the world.

17:47 There is delight in the Brawn garage as the team celebrates both world championships.

"It's really amazing. My voice has gone now! It was such an awesome race. I'm world champion baby! "
Jenson Button, world champion speaking to BBC TV

17:50 The rain showers, still building in the area, held off in the end but it mattered little for dramatic conclusions to the titles.

17:51 Our round up of an action-packed Brazilian Grand Prix is now available:

Button clinches title as Webber wins in Brazil

17:55 Jenson Button is the 2009 FIA Formula 1 World Champion.

His drive to the title today was set when lap one produced carnage in the middle of the field. The Briton cleverly avoided all the mischief to resume after the safety car period in ninth. Nico Rosberg's disappearance and Barrichello's downfall put him in an increasingly strong position throughout the race.

It's party time in the Brawn garage and the team will deservedly celebrate an astounding season tonight.

This was the Brazilian Grand Prix on AUTOSPORT Live. Thanks for being with us throughout the chaos of the weekend. We now have a free-for-all to end the season in Abu Dhabi in a fortnight. Our weather forecast will be available on Monday 26th October.