From GMM

The darkest cloud yet has just moved above the health of Donington's plans to host the next 17 British grands prix.

At Britain's formula one round last month, having previously ruled out ever returning to Silverstone, F1 chief executive Bernie Ecclestone revealed that if Donington is not ready to take over in 2010, the Northamptonshire venue will step in.

Now, the 78-year-old Briton concedes that Donington's chances of even hosting the race every year in 2011 and beyond are in doubt.

Amid speculation Donington CEO Simon Gillett is struggling to pull together the funding for his F1 project, Ecclestone raised the prospect of a scheme whereby the two British circuits annually alternate hosting the British GP.

"If they don't do it, Donington will get together with Silverstone," he told the Independent on Sunday newspaper.

The billionaire seemed to indicate that Silverstone is more likely than Donington to host the event in 2010.

"If Silverstone do all the things they promised me they are going to do, we are going to be at Silverstone," Ecclestone, who has imposed a September deadline for Donington to gets its funding ready, added.

The alternating scheme is a growing trend in F1, with Germany's event shared between Hockenheim and the Nurburgring, while Suzuka and Fuji were scheduled to share the Japanese grand prix every year before the latter pulled out of the sport.

However, Damon Hill, president of the Silverstone-owning club the BRDC, said he is not in favour of the share idea.

"I think it's an insult," he said. "It's another absurd step to try and squeeze as much profit and as much benefit for the commercial rights holder. It's not a long term strategy."