Button: Williams Contract Not Binding

"Initially, we don't think the contract is binding," the 25-year-old told reporters at the Hungarian Grand Prix on Thursday when asked how he proposed to get out of his commitment.

"Secondly, I don't think any team wants a driver that would like to be racing for somebody else. I can't see why anybody would want that."

Button was reminded that his position was the opposite of what he said last year when he wanted to join Williams and was thwarted by BAR.

The two Formula One teams fought a legal battle over his contract and BAR won, forcing him to stay another year despite the driver's insistence that he wanted to return to the team that gave him his Grand Prix debut in 2000.

Williams are convinced they have a watertight deal for 2006 but Button said the circumstances had changed since then, with Honda buying 45 percent of BAR and Williams's exclusive partnership with BMW ending.

"This is a crucial decision for me," he said.

"The choice I have made is the right one for the future. This is a decision that I think will change my career so I have to make it.

"I've sat down with Frank (Williams) and we've had a few chats about it and I've told him the way that I feel. I don't know if he understands but I need to be with the best team I possibly can be with," added Button.

Championship Bid

Button finished third overall last year but has yet to win a race in 94 starts.

"I've been in Formula One for six years now and I'm ready to win races and challenge for the World Championship and I can't wait another three years, building another team up," he said.

"I need to be with a team that's capable of doing it in the short term."

Button said the key was to be with a team that had a manufacturer fully involved as owners, not just as an engine supplier.

He said the key to his determination to stay at BAR, after having been previously equally adamant about leaving, was Honda's decision to invest heavily.

The tough season, with BAR disqualified from the San Marino Grand Prix and then barred for two races, had also shown him just how strong the team were.

"I was amazed really. I went to the factory after Barcelona and saw the whole team, and to see how determined they were to turn it around - I was very surprised. It just shows how well everyone works together," said Button.

The English driver said he had made a mistake last year but was hopeful that an agreement could be reached between BAR, who see Button as the face of their future, and Williams without recourse to lawyers.

"He (Frank) has given a small hint that we can negotiate," he said, refusing to confirm speculation that he might be willing to use his own money to help matters along but suggesting it was a possibility.