Formula 1 World Championship leader Jenson Button has insisted that his focus is fully on 2009, despite increasing speculation about his future in the wake of his remarkable start to the present campaign - and he is adamant that his 'only interest' is in having a competitive car underneath him.

The British star certainly has that in the Mercedes-powered Brawn GP BGP 001, in which he has commandingly swept to victory on all-bar one occasion thus far this season, triumphing five times out of six to arrive in Istanbul for this weekend's Turkish Grand Prix 16 points clear of his nearest challenger in the drivers' title chase, team-mate Rubens Barrichello.

Following two years spent in the doldrums with chronically uncompetitive machinery at his disposal, Button's renaissance in 2009 has prompted much talk within the paddock about where he is likely to be driving next season, with potential openings at traditional 'leading' teams Ferrari and McLaren-Mercedes amongst others.

Whilst he was frequently pilloried earlier on in his F1 career for having prioritised the size of his retainer over the speed of his car, however, the 29-year-old agreed to take a considerable pay cut this year merely to help the ex-Honda F1 operation stay afloat and make the starting grid at all.

Brawn GP CEO Nick Fry hinted last time out in Monaco - scene of yet another flawless lights-to-flag success - that with more sponsorship deals in the pipeline, Button's loyalty to the cause could well be rewarded with a significant hike in salary in 2010, making it clear that the team wishes to tie its star driver down for the remainder of his grand prix career. The Frome-born ace, though, has re-iterated that his mind is firmly on the job in-hand, and not anything that may lie beyond.

"I don't want to talk about anything that is irrelevant at the moment," he is quoted as having said by Speed TV. "I am very happy; all I think about is racing. I haven't spoken to anyone in the team about it because I'm not interested.

"I'm here to race - I don't want to talk about money. I continued with this team because I thought the car would be competitive, and that's my only interest at the moment."