Sir Jackie Stewart says he is concerned for Silverstone's future following Bernie Ecclestone's acquisition of the rights to the British Grand Prix.
Stewart, president of Silverstone owner the British Racing Drivers' Club, said the track could lose its income.
Advertising giant Interpublic's decision to give up the F1 rights means it can end its deal to lease the circuit in 2007 rather than 2015.
Stewart said: "We have no other major source of income beyond that tenancy."
Stewart said the BRDC had not "had a business discussion yet with Interpublic. We have been in dialogue, but there has been no decision on [the possibility of Interpublic ending the lease early]."