It has finally been officially confirmed what has been speculated for some time that the WilliamsF1 team and Cosworth have signed a partnership deal for 2006.

In a statement released by the team Frank Williams and Cosworth CEO Tim Routsis spoke of the new partnership.

Frank Williams said: "Cosworth is a leading global authority on V8 engine technology. Next year is a brand new start for all concerned given 16 years of V10 engines. Some teams and manufacturers have absolutely no experience of V8s while others enjoy only limited experience.

"Cosworth, however, have excelled both historically, as well as in contemporary V8-powered international motorsport. The evidence of Cosworth's V8 progress we have seen so far validates completely the expectation we have of enjoying a class-leading package given next season's engine rule changes."

Tim Routsis, Cosworth's CEO, said: "Our experience and track record with V8 engines is unrivalled and we are naturally delighted to be alongside one of the most uncompromising and pure-spirited teams in Formula One. We have been working on the development of next year's V8 since April 2004 and right from the onset, our performance targets have been set very aggressively.

"We are confident that our blue-chip partnership with WilliamsF1 can augment the record of winning the Championship every decade since the 1960s. We have developed the 2006 Cosworth V8-CA engine with nothing but front-running success in mind for both the near and long-term. The involvement of Cosworth's sister company, Pi, has been instrumental in achieving this outcome."

And Patrick Head, Williams's Director of Engineering, added: "Williams has made this partnership decision purely on technical merit. Among the range of options we considered, Cosworth are very well advanced with existing development and are committed to taking the potential of this collaboration further.

"Our engineers have already reflected on the very productive and highly motivated nature of the relationship between our two organisations. We speak the same racing language and both have something to prove next year and there can be no greater motivation to succeed."