Formula 1 owner Liberty Media has hit out at what it regards as "posturing" by British Grand Prix promoter the BRDC.

It is believed that the Silverstone-owning British Racing Drivers' Club has now told Liberty that it is exercising a 2019 break clause in its race deal.

Liberty says that decision is "regrettable".

"Our focus is to preserve the British Grand Prix," a Liberty spokesperson said.

"We will carry on negotiating with the promoter in good faith and in private to reach a fair and equitable solution."

Silverstone claims that, despite attracting full crowds, it is unable to break even due to the current contract fee negotiated by ousted F1 supremo Bernie Ecclestone.

However, insiders have warned that wagering on a renegotiation could backfire.

Liberty is hosting a demonstration of F1 teams and drivers in London this week, amid new rumours that Silverstone could be replaced by a street race in the capital.

"London is always open to hosting the world's best sports events," The Times quotes London mayor Sadiq Khan as saying.

"We have had no approach from F1 about a race. We would need to consider the full impact of a race weekend on air pollution and safety."

This year's race takes place at Silverstone on Sunday.