The united stance of carmakers and teams in talks with Bernie Ecclestone over Formula One's future looked less solid last night after Williams confirmed they remained uncommitted to either side.
The five carmakers, who are planning their own series from 2008, and seven of the ten teams met in Germany last week and issued a statement on Wednesday announcing a " binding agreement."
It said the five manufacturers and their teams were determined "to race together only in a series which satisfies the fundamental principles of a clear and equitable world championship."
Williams said they had not agreed anything, however.
"It is correct to say that Williams is not yet a signatory to the (manufacturers') agreement, but we do not consider it appropriate to discuss the reasons for this at the moment," a team spokesman said.
The manufacturers - DaimlerChrysler's Mercedes, Renault, BMW, Honda and Toyota - are at odds with Formula One supremo Ecclestone over the way the sport should be run once an existing commercial agreement expires at the end of 2007.
They want a far bigger share of the money and a 'level playing field'.
Renault and Toyota wholly own their teams while BMW have taken over Sauber. Mercedes own 40 per cent of McLaren while Honda have a 45 per cent stake in BAR.
Although seven teams attended the meeting, and all appeared to be in agreement, it has since become clear that Williams and Minardi remain outsiders.
Minardi boss Paul Stoddart has sold his team to Red Bull, whose Austrian billionaire owner Dietrich Mateschitz is in Ecclestone's camp.
Mateschitz says Minardi would become the fourth team to agree a deal with Ecclestone after Ferrari, Jordan and Red Bull.
It was claimed at the weekend that Ecclestone had won over Fiat-owned Ferrari with a 'sweetener' of $100 million and was likely to offer Williams about half that.
Williams are losing partner BMW and main sponsor Hewlett-Packard at the end of the year and will have to pay Cosworth for their engines in 2006.
Ecclestone said he had offered the teams 50 per cent more cash from 2008 if they signed a new 'Concorde Agreement'.
* BAR-Honda have been forced to call a temporary halt to their bid to set a new Formula One speed record.
The Brackley-based team aim to hit 400kmh, almost 250mph, on the legendary Bonneville salt flats in a modified, but still track-legal, Formula One car.
The attempt was abandoned after rain made the salt flats treacherous.