Formula One was plunged into fresh chaos last night when it emerged that Renault had held emergency talks on Wednesday over joining Toyota in exiting the sport.
The French manufacturer was said to be considering whether to continue running a team, reduce supplying engines or to withdraw altogether.
Toyota became the third team in 11 months to pull out, a decision met with outrage by the FIA, which would investigate the legal implications of the decision, despite Toyota having signed a new Concorde agreement.
“Urgent clarification is now being sought from the Toyota F1 team as to its legal position in relation to the championship. This will have a direct bearing on the admission of any future 13th entry,” a statement by the world motor sport’s governing body said.
Bernie Ecclestone, the sport's commercial rights owner, added: "They did sign the agreement knowing exactly what it meant. Fortunately we have other teams coming."
The team was withdrawn after Toyota Motor Corporation returned its worst sales figures in 32. Toyota entered F1 in 2002 and did not win a race in 139 attempts, despite a substantial budget.
News of Toyota's withdrawal sparked an outburst by Ferrari, who claimed the sport's rulers had "waged war" on the big car-makers.
"In reality, the steady trickle of desertion is more the result of a war against the big car manufacturers," a Ferrari statement said.
"Formula One continues losing important parts. In exchange, if one could call it that, Manor, Lotus, USF1 and Campos Meta arrived. You might say 'same-same', because it is enough if there are participants. But that's not entirely true."
Acting team principal, Bob Bell, and managing director, Jean-Francois Caubet, attended Renault’s board meeting in Paris. However, according to a Renault spokesman, the summit had been planned for weeks.
There is an irony in the likelihood that Toyota's withdrawal will allow Sauber back in. BMW had earlier said they would be leaving at the end of this year.
But Sauber may be saved by Toyota’s departure.
As BMW did not sign the Concorde agreement unlike Toyota, their efforts to sell Sauber were jeopardised as any new owner would have to get unanimous agreement from competitors to increase the number of teams to 14 if. Such unanimity was not forthcoming.