Final positions:
1 JP Montoya (Williams)
2 K Raikkonen (McLaren)
3 R Barrichello (Ferrari)
4 F Alonso (Renault)
5 R Schumacher (Williams)
6 T Sato (BAR)
7 M Schumacher (Ferrari)
8 F Massa (Sauber)

Lap 71: Juan Pablo Montoya wins by exactly one second from Kimi Raikkonen. Rubens Barrichello is third, Fernando Alonso gets home in fourth followed by Ralf Schumacher, Takuma Sato and Michael Schumacher.

Lap 70: Alonso will be safe in fourth and Sato looks likely to hold off first Ralf and then Michael Schumacher. But no, Ralf gets past Sato's BAR.

Lap 69: A small mistake from Raikkonen gives Montoya breathing space as the ends nears.

Lap 67: Takuma Sato is having a bit of a look down the side of Fernando Alonso in fourth. Up front, Kimi Raikkonen is inching towards Juan Pablo Montoya.

Lap 65: The Schumacher scrap is giving Sato the chance to shake them off for the moment.

Lap 63: Michael Schumacher is itching to make a move on his brother but Ralf is refusing to play happy families.

Lap 62: Montoya is holding at about one second clear of Raikkonen with Barrichello solid in third, 20 seconds back.

But Alonso is in danger of losing his fourth place with a three-car train of Sato and the Schumachers thundering up behind.

Lap 59: Montoya is being stalked by Raikkonen as the pair set up a grandstand finish.

Lap 56: Montoya leads by just over 1.4 seconds from Raikkonen. There is a titanic struggle going on for fourth with Alonso, Sato and both Schumachers separated by little over 1.5 seconds.

Lap 55: Takuma Sato in the BAR Honda pits from third as Raikkonen finally goes in for his third stop. A quick one takes the Finn into second on the track.

Lap 54: Raikkonen leads by 18 seconds over Montoya.

Lap 52: Fernando Alonso gets back past Ralf Schumacher into fourth.

Lap 50: Michael Schumacher pits from fourth.

Lap 49: Juan Pablo Montoya sets a new lap record and then dives in for his third pit stop. Rubens Barrichello comes in for his third.

Lap 47: Third-placed Fernando Alonso makes his second stop. Ralf Schumacher pits for his third time.

Lap 46: Jacques Villeneuve and Jarno Trulli pit.

Lap 45: The battle for third, fourth and fifth is hotting up as Alonso, Ralf Schumacher and Barrichello are separated by only 2.5 seconds.

Lap 42: Ralf Schumacher is stuck behind Fernando Alonso as he tries to climb to third.

Lap 41: Race leader Montoya and Raikkonen are lapping at the same time as the race enters a neutral period.

David Coulthard makes possibly his last pit stop as a McLaren driver.

Lap 39: Michael Schumacher is just over six seconds behind Takuma Sato in seventh.

Lap 36: Juan Pablo Montoya leads by just over five seconds from Raikkonen with Alonso, who has still not stopped for a second time, 17 seconds back.

Lap 34: Giancarlo Fisichella pits and comes back out down in 11th.

Lap 33: Felipe Massa makes a stop but goes back out on dry tyres.

Lap 32: Takuma Sato makes a mistake and Rubens Barrichello gratefully accepts the gift to move into fifth.

Lap 31: Rain is coming down now, which could play into Alonso's hands as he has not yet made a second pit stop.

Lap 28: Michael Schumacher pits from fifth place. Race leader Raikkonen also goes in.

Lap 27: Sato, Barrichello and Montoya pit.

Lap 25: Minardi's Zsolt Baumgartner pits as does Ralf Schumacher of Williams.

Lap 24: Michael Schumacher is climbing all over the back of the Renault of Fernando Alonso.

Lap 23: Jaguar's Mark Webber smashes into team-mate Christian Klien and is forced to retire with a shattered wing. Klien pits to get a new nose fitted.

Lap 22: Juan Pablo Montoya leads by just under four seconds as fifth-placed Rubens Barrichello sets another fastest lap.

Lap 21: Jacques Villeneuve is the last driver to pit, meaning Michael Schumacher gains another place.

Lap 18: Fernando Alonso makes his first pit stop as Juan Pablo Montoya responds with the fastest lap. Alonso emerges into sixth place.

Lap 17: Nick Heidfeld spins his Jordan on turn 10 and is pushed off the track. Rubens Barrichello smashes the lap record.

Lap 16: Fernando Alonso and Jacques Villeneuve are the only drivers not to have pitted so far.

Lap 14: David Coulthard pits to drop out of the picture as Michael Schumacher nudges to eighth.

Lap 12: Juan Pablo Montoya cuts Fernando Alonso's lead to under eight seconds. Raikkonen is 1.6 seconds back. David Coulthard breaks the track record.

Lap 11: Michael Schumacher is getting held up by David Coulthard in the scrap for eighth place.

Lap 6: Raikkonen, Montoya, Sato all pit for slick tyres as the track dries out. Raikkonen leaves first but Montoya edged past into turn four.

Barrichello pits to leave Felipe Massa in the lead but in turn the Brazilian goes in, so Fernando Alonso takes over in front.

Lap 4: Rubens Barrichello surges past Kimi Raikkonen to take the lead as BAR's Jenson Button retires with a smoking engine.

Lap 3: Michael Schumacher spins after a close call with Jaguar's Christian Klien.

Lap 1: Rubens Barrichello gets off to a good start but Kimi Raikkonen overtakes him two corners later.

Jenson Button moves past Felipe Massa into third as Michael Schumacher cruises into 10th from his 18th starting position.

The cars set off on the formation lap on a greasy track as the drizzle continues to come down.

Coulthard and Villeneuve are still on dry tyres while Michael Schumacher is on intermediate Bridgestones. Montoya is one of those already favouring wets.

Minardi drivers Bruni and Baumgartner pit.

With 10 minutes to go to the start at 1800 BST, the light drizzle of the last hour is getting slightly heavier in Sao Paulo.

A damp track would favour those running Michelin tyres - all of the top teams except Ferrari - but if a downpour develops the Bridgestone's of the champions will perform better.

Rubens Barrichello is aiming for his first victory at his home Grand Prix after failing to finish the race nine times.

Lap Interlagos with Jarno Trulli

The Brazilian, who grew up around the corner from the Interlagos track, is on pole position in his Ferrari, ahead of Juan Pablo Montoya's Williams-BMW and Kimi Raikkonen's McLaren-Mercedes.

World champion Michael Schumacher starts from the back after being penalised 10 grid positions for changing engines.

The German was forced to switch to the spare Ferrari after a 165mph crash in practice on Saturday morning.