World champion Casey Stoner has topped off an imperious weekend's riding to win his second consecutive British Grand Prix and reignite his MotoGP title defence.

It was a case of cruise control for the Australian as he exploded off pole position to dominate the field in dry conditions and finish in 44min 44.982sec, leaving Valentino Rossi and Dani Pedrosa in his wake.

And Stoner's second MotoGP victory of the season could not have come at a better time, as it sees him closing the gap to 45 on standings leader Rossi as the championship enters the half-way stage.

"Now we know we can fight for it (the title) now. We hope it's game on now, we didn't think this was a track we could do well on," said Stoner, who was fastest in Friday's practice sessions and Saturday's qualifying.

"Whether we can chase them (the series leaders) down is going to be difficult as they are finishing high in every race."

Stoner's runaway victory mean Rossi and Pedrosa had to contend with a battle for second and third over five seconds behind, which the Italian - in his 200th grand prix race - won after a tough battle.

But Rossi was typically relaxed after the race, praising his old adversary Stoner and was confident of his chances of landing an eighth world title.

"We tried for victory but Casey was too strong. I'm back on the podium here in front of large crowd and in front of Pedrosa, so I have added four more points to my lead over him," said Rossi, who now has 162 championship points.

"That is 200 GPs and I am still learning! We wanted to try and win the 200th, but it is good to be on podium and at top of title race."

Pedrosa's third-place and his consistent podium positions in this year's championship means he remains second in the overall standings on 151.

"I had the pace to take Rossi and I thought for a moment I had him but made a big mistake on a chicane and then started to slow down," said the Honda rider, winner of CatalunyaGP earlier this month.

"He was simply faster, I have no excuses, we will try in the next one (Dutch GP, next weekend) to be faster in last five laps. I've no idea why the pace on the bike dropped, maybe it was the changing of direction."

But it was cruel disappointment for James Toseland, who had hoped to put on a good show for the home crowd, after he spun off in the opening seconds before retiring after completing only one lap.

AAP