Although much has been made of a meeting due to take place at BMW's HQ in Munich on Tuesday, the company's motorsport boss, Mario Theissen, has said that details of the German manufacturers long-term F1 plans will not be known until the end of next month.

There is currently much speculation that BMW is looking to purchase Sauber and enter its own F1 team, though to all intents and purposes it, along with the other manufacturers, intends heading to the breakaway series in 2008.

BMW had looked at forming its own F1 team in the past, with former motorsport boss, Gerhard Berger, a keen fan of the idea.

BMW and Theissen are currently attempting to play down the rumours, claiming that all that is on the table is a possible engine deal with the Swiss team, as opposed to a buy-out. The German manufacturer is also keen to make it clear that is has at least another year of its contract with WilliamsF1 to run.

"I can only say we are very focussed on working with WilliamsF1," said Theissen at the weekend. "We are talking to Sauber primarily on engine supply for next year. However, everything beyond that is speculation."

Looking ahead to the forthcoming meetings, he added: "We will discuss our strategy in June. Don't expect a result next week, rather at the end of June.

"It is an internal discussion," insisted the German. "As soon as we have a decision we will certainly communicate it."

Thanks to a number of factors, not least constant improvements to the WilliamsF1 FW27, the Grove outfit has had three podium places in the last two races, in addition to pole-position at the Nurburgring, a track which has a special place in BMW's heart.

However, aside from the rumours linking BMW with Sauber, there is mounting speculation that WilliamsF1 is already seeking a partnership with Toyota, the English team having enjoyed mixed success - one drivers' title and two constructors' - with its great rival, Honda, in the mid 80s, before the Japanese company went off to form an alliance with McLaren, and Lotus.