By Andrew Benson
McLaren could pull out of Formula One if the dispute over the sport's future is not resolved to their satisfaction.
McLaren are among the teams fighting for a bigger share of F1 revenues
Team principal Ron Dennis said: "If the status quo exists in F1, we will not participate in it in 2008."
Dennis' remarks are a reflection of the seriousness of the biggest political crisis to hit F1 in more than 20 years.
Nine of the 10 teams and five of F1's car manufacturers are at loggerheads with world champions Ferrari and the sport's governing body the FIA.
Dennis said McLaren, the second most successful team in F1 history, were so unhappy with the way the sport was being run that they were looking at ways to ensure they could survive financially if they did not race in F1 in 2008.
They and eight other teams have signed up to a set of guiding principles drawn up by car companies DaimlerChrysler, Honda, BMW, Toyota and Renault which outline the way they want the sport to be run.
The five car manufacturers have threatened to set up a breakaway championship in 2008.
But world champions Ferrari have committed to race in F1 until 2012 after signing an agreement with the sport's commercial boss Bernie Ecclestone and Max Mosley, the president of the FIA.
The contracts that bind the teams to F1 expire at the end of 2007.
The car manufacturers want a bigger share of the sport's income, a fairer distribution of income and more say in its management.
There is discomfort at what the other teams see as the close relationship between Ferrari and the FIA, and at some of the promises made to the Italian team in return for their commitment to F1 beyond 2008.
McLaren's chief operating officer Martin Whitmarsh added: "We don't believe there will be two series, and if the manufacturers and teams stay together, hopefully it (the alternative proposal for F1's future) will be something Ferrari will want to align themselves with.
"We think transparency, impartiality, fairness, appropriate governance and stability are critical.
"Given the companies which now invest significant amounts in F1, F1 has to grow up. We won't keep Honda, Toyota and so on in F1 if they perceive a lack of clarity and fairness - and they do."
Dennis, whose team is 40% owned by DaimlerChrysler, said the teams were effectively being excluded from the process by which decisions about fundamental changes to the sport were made.
Dennis is not happy with the way F1 is being run
He added: "I do not believe the voting members of the FIA have any comprehension of the dissatisfaction felt by all the manufacturers and the nine teams at the current situation in F1."
Whitmarsh said his and Dennis' comments were "not aimed at Bernie, Ferrari or the FIA".
Dennis added: "Ferrari are a magnificent Grand Prix team, are steeped in tradition and they would most definitely be missed if they are not part of whatever future holds for Grand Prix racing.
"But they should not be put into a position that provides them with the ability to control change or receive a disproportionate amount of income compared to the other teams."
He said McLaren would probably race elsewhere in 2008 "if there is not a level playing field" - as long as he can set the company up by then so that it could survive without racing in F1.
Whitmarsh also cast doubt on the nature of the contract signed by Ferrari, which was claimed by Ecclestone to be an extension of the Concorde Agreement, the secret document by which F1 is governed.
Whitmarsh said: "We don't know what Ferrari have signed up for, and we don't believe they do.
"They have entered into a 'heads of agreement'. They have not signed a comprehensive agreement with the commercial rights holder (Ecclestone) or the FIA."