The post-qualifying car weights published by F1's governing body the FIA have sent out an ominous warning to 19 of the drivers lining up on the starting grid for the British Grand Prix at Silverstone on Sunday - Sebastian Vettel is going to be very, very hard to beat indeed.

The young German has looked in scintillating form from the word 'go' around the popular Northants circuit, and after an earnest challenge from Red Bull Racing team-mate Mark Webber, he broke the Australian's spirit to sweep to a second straight pole position after that achieved in Istanbul a fortnight ago - his third of the 2009 campaign. What's more, it also now transpires that his is the heaviest car inside the top ten too, underlining the brilliance of his lap - more than three tenths out of reach of anyone else.

Webber, indeed, is carrying some 7kg less fuel than the sister RB5, meaning the New South Wales native's chances of pulling off his maiden victory in the top flight on Sunday look slim, barring any slip-ups from the pole-sitter. He is at least, however, set to run longer into the race before making his first pit-stop than Brawn GP rival Rubens Barrichello, who pipped him to the outside slot on the front row by a scant twelve hundredths of a second - meaning a second one-two of the season for the energy drinks-backed outfit is far from out of the question.

For runaway world championship leader Jenson Button, meanwhile, there is only further misery, with no driver ahead of him on the grid running lighter, and the two directly behind him - Nico Rosberg and Timo Glock - on heavier fuel, meaning the British star could have his work cut out if he is to reward his adoring fans with a rostrum finish on home turf.

Elsewhere inside the top ten, Kazuki Nakajima's stellar showing was explained in part by the Japanese ace carrying the lightest fuel load in the field - but Williams team-mate Rosberg looks good value in seventh, and Jarno Trulli in the leading Toyota similarly did an excellent job to grab P4. For former world champions Kimi Raikkonen and Fernando Alonso, by contrast, there could be a long afternoon ahead from the fifth row - both are due to stop early, leaving them at the mercy of the more heavily-fuelled drivers in their wake.

The full list is as follows (their actual starting position is in brackets at the end):

Kazuki Nakajima Williams-Toyota 652.5kg (5th)Kimi Raikkonen Ferrari 654.0kg (9th)Fernando Alonso Renault 654.0kg (10th)Rubens Barrichello Brawn GP-Mercedes 657.5kg(2nd)Jenson Button Brawn GP-Mercedes 657.5kg (6th)Jarno Trulli Toyota 658.0kg (4th)Mark Webber Red Bull Racing-Renault 659.5kg (3rd)Timo Glock Toyota 660.0kg (8th)Nico Rosberg Williams-Toyota 661.5kg(7th)Nick Heidfeld BMW-Sauber 665.5kg (15th)Lewis Hamilton McLaren-Mercedes 666.0kg (19th)Sebastian Vettel Red Bull Racing-Renault 666.5kg(1st)Giancarlo Fisichella Force India-Ferrari 668.0kg (16th)S?bastien Buemi Scuderia Toro Rosso-Ferrari 672.5kg (20th)Felipe Massa Ferrari 675.0kg (11th)Nelsinho Piquet Renault 682.5kg (14th)S?bastien Bourdais Scuderia Toro Rosso-Ferrari 687.5kg (17th)Robert Kubica BMW-Sauber 689.5kg (12th)Adrian Sutil Force India-Ferrari 692.0kg(18th)Heikki Kovalainen McLaren-Mercedes 695.5kg (13th)