Formula One supremo Bernie Ecclestone has threatened to switch the British Grand Prix from Silverstone to Donington Park after 2009.

"We are discussing the possibility of reaching an agreement with Donington to host the British Grand Prix," Ecclestone told The Times.

"We are trying to save the British Grand Prix and we want it to be staged at a venue which befits an event of its stature. I've been in negotiations for a long time and whether or not we're going to do a deal with Donington or Silverstone, I don't know."

"Donington have said they are going to build everything we want. Have they got the money? Only time will tell. But I think there is more chance of Donington having the money than the BRDC," added the Briton.

Silverstone, which hosted the first championship race in 1950, is owned by the British Racing Drivers' Club who are planning to redevelop the pits and paddock complex to bring the circuit in line with other more modern facilities.

Formula One has raced before at Donington, with the European Grand Prix in 1993, but Ecclestone's comments are likely to be seen more as a means to put pressure on the BRDC in ongoing negotiations.

Ecclestone has regularly threatened to take the British Grand Prix away from Silverstone in the past and his latest comments come in the build-up to this year's race at the circuit on July 6.

Donington, which hosts the British motorcycle grand prix this weekend, would require considerably more updating to bring it up to Formula One standards while also being plagued by severe traffic congestion.

Silverstone said in a statement that they were on course to build a world-class facility that fully complied with Ecclestone's requirements.

"Many countries and venues are competing for a limited number of dates on the F1 calendar, but we are making good progress towards delivering what we set out to achieve," said Silverstone Circuits managing director Richard Phillips.

"We are confident that an agreement can be reached with FOM (Formula One Management) to secure the long term future of the British Grand Prix at Silverstone."