Terse Ecclestone defends Renault ruling
Formula 1 chief Bernie Ecclestone has warned the Donington Park circuit it is running out of time to ensure it hosts the 2010 British Grand Prix.
Donington, which closed this week to begin preparations to welcome F1 next year, has faced legal and financial hurdles since being given the race.
"Donington have had 'a bit more time' three times," Ecclestone told BBC Sport. "They can't have much more."
However, he added Silverstone was not a guaranteed stand-by option for 2010.
Urging Donington to step up preparations, Ecclestone said: "If it's going to be Silverstone - and there's no guarantee it will be, if it's not Donington - they want to get on, get the race prepared, and sell tickets."
That contradicts remarks Ecclestone made at the British Grand Prix in June, when he said Silverstone would remain as host if Donington was not ready.
It has been reported that Ecclestone expects proof of funding and completed plans from Donington's chiefs by the end of next week, which extends his initial deadline - the end of September - by several days.
"I think we have given them until 3 October," Ecclestone was quoted as saying in Singapore on Thursday.
"Their problem is a financial one - it is them getting the money together."
Donington faces an outlay of £80m to bring the Leicestershire circuit up to F1 standards and, while some work has been completed, the last event on the current track only finished on Wednesday.
Everybody's entitled to their own opinion, aren't they? Why should his opinion be more important than mine? He doesn't come to races, he doesn't know the people involved
Bernie Ecclestone replies to comments from Sir Martin Sorrell
Other facilities at Donington will remain open while renovation takes place.
Meanwhile, Ecclestone hit back at comments from Sir Martin Sorrell, a board member at Formula 1 shareholders CVC, who criticised the F1 boss in the Daily Mail on Saturday.
"First we had Hitler did good, now we have cheating is acceptable," Sorrell told the newspaper in response to Ecclestone's observation that Flavio Briatore's punishment for the Renault race-fixing scandal had been "quite harsh".
"His latest comments are yet another example, I'm afraid, of Bernie being totally out of touch with reality," said Sorrell.
But Ecclestone told the BBC: "The comments I made about Hitler were taken completely out (of context) and I apologise. As far as cheating, I haven't made any comments.
"Everybody's entitled to their own opinion, aren't they? Why should his opinion be more important than mine? He doesn't come to races, he doesn't know the people involved."
With reference to the punishment for former Renault boss Briatore, who has received a life ban from the sport, he added: "Giving somebody life - they don't even do that for murder."
Ecclestone also confirmed there were doubts over the composition of the 2010 F1 grid, admitting one of the new teams expected to make their debut next season, US F1, were "a doubt".