McLaren's Lewis Hamilton has vowed to fight for the Formula 1 title, despite ruling himself out 24 hours earlier.

Hamilton struggled for pace at the European Grand Prix, finishing fourth to leave him 89 points adrift of leader Sebastian Vettel in the championship.

"It's finished really. In the sense of the title it's almost over," said Hamilton on Sunday.

But on Monday, Hamilton said on Twitter external-link : "My team will never give up & I will never give up."

His latest comments come after the McLaren driver ruled out challenging for victory on home soil at next month's British Grand Prix.

"I'm not looking forward to the race because the desire to win is even greater because it's my home country," said Hamilton.

"But we're just not quick enough to win there. I think we'll really struggle."

From the British Grand Prix onwards, the use of off-throttle blowing of diffusers, which help to increase downforce by blowing hot gases over the rear of the car's floor while the driver is not pressing the accelerator, will be banned.

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While nobody knows for sure how the ban will affect the pecking order, Hamilton is downbeat about the impact the ban will have on his team.

"I'm really not looking forward to it," added the 26-year-old Englishman, who finished second behind Mark Webber at last year's British Grand Prix.

"Of course, I'm really looking forward to seeing the fans because they always put a spark in the weekend and make it that much brighter.

"And I'll be going there as prepared as I can, racing as fast as I can, but we're not fast enough.

"[In Valencia] it feels like we've taken a step back in terms of performance or the others have taken a step forward and with the regulations changing I personally think we're going to take another step backwards.

"We'll have to see how the ban affects us but I'm a little bit nervous about it. I think we might be affected more than the two teams ahead of us [Red Bull and Ferrari]. It will be even worse for us.

"I don't really have any expectations. I hope that we can finish ahead of one of the Ferraris there. That would be a positive."

Hamilton's McLaren team-mate Jenson Button, who finished sixth in Valencia, has urged the team to increase the rate of development on the car ahead of Silverstone.

"We need some good upgrades," said the 2009 world champion. "We need to get our heads down and improve the car.

"Aerodynamically I think we need an improvement for Silverstone because we're not moving forward and that's what we need to be concentrating on.

"I do know of some new parts that are coming but I think we need more. We need to take some risks because behind us is a big gap, in this race [Valencia] anyway, to the Mercedes, the Ferraris are in front of us and the Red Bulls are miles away."