Red Bulls set practice pace

The threat of a breakaway series may be in the offing but there is still a Formula One world title at stake. In front of his home crowd at Silverstone, Jenson Button is aiming to build on his 26-point lead at the top of the drivers' standings but it would seem Red Bull Racing are aiming to steal his thunder.

Sebastian Vettel and Mark Webber were a comfortable one-two at the end of the opening practice session at the Northamptonshire track.

Webber led the way until the dying moments with a lap of one minute 19.682 seconds, only to see out the 90-minute period with a degree of frustration.

Initially, Vettel knocked Webber off top spot by 0.282secs and then, as the Australian pulled into his pit box after completing his final in-lap, wisps of smoke were seen coming from the engine.

Despite that, the Red Bull duo - with their cars sporting a new and significantly improved package - were head and shoulders above the rest of the field.

Button, with his sights on setting Silverstone alight with a seventh win from eight races, was third quickest, but finished 0.545secs adrift.

Brawn GP team-mate Rubens Barrichello was in close attendance on a circuit he loves, just a further 0.015secs behind the 29-year-old Briton.

Renault's Fernando Alonso and Felipe Massa in his Ferrari were just over a second behind young German Vettel, with Jarno Trulli in his Toyota seventh.

As for world champion Lewis Hamilton, who won the race here last year by a remarkable margin of 68 seconds in the wet, he was eighth fastest in his McLaren, 1.1250secs down.