Toyota F1 boss John Howett has said that there is no reason at all to question whether or not the Cologne-based operation will remain in the sport in 2010.

There had been speculation following reports last weekend at the European Grand Prix that the Japanese car manufacturer had yet to sign off the budget for its F1 operation that it might join BMW and Honda and leave.

However Howett insisted on Friday that the budget is always only 'fundamentally' approved in November and that the squad will be there in 2010, as well as in 2011 and 2012.

"I mean there is a lot of speculation about a lot of teams," Howett replied when asked about the teams' future in the countdown to this Sunday's Belgian Grand Prix at Spa-Francorchamps. "[But] I have no reason at all to question that Toyota won't be here for the next three years and no information to the contrary.

"I think there was some story about budget [last weekend in Valencia] and fundamentally our budgets are always approved in November.

"I genuinely was explaining that this year it was a bit more difficult to know what is likely to be approved and we have to accept that there is a very tough economy out there."

Meanwhile with reports suggesting Williams F1 may want to end its engine supply deal with Toyota early and switch to Renault powerplants next year, Howett added that it wasn't necessarily important for them to have a customer.

He also noted that if Williams do want to go elsewhere, Toyota would not stop them from doing so.

"I think we did it [started supplying engines to customers] really because we wanted to contribute to F1," he explained. "I think at that time Ferrari were supplying and nobody else did. I think we are very willing and open to supply. We basically have an agreement with Williams to supply in 2010 but I think Toyota generally is normally a sensible company and if somebody does not wish to continue trading with you, we will consider favourably that decision.

"But, as such, as I sit here we do have a binding contract to supply Williams with engines in 2010. But we don't gain a huge amount of material information from it. We are not developing a new engine. Therefore, I am not sure if we gain a material amount from losing supply at this current time."

How likely it is that Williams will switch remains to be seen, but the team did of course enjoy a lot of success with Renault in the 1990s.

"The engine situation is still a work in progress. I think we are relatively clear on which direction we want to go in but obviously it is not finalised yet," was all Williams chief executive, Adam Parr had to say on the matter.