SILVERSTONE, England, July 8 (Reuters) - Sunday's successful British Grand Prix should serve as a wake-up call for Silverstone's owners, according to Formula One supremo Bernie Ecclestone. The Briton said he was delighted with the capacity 85,000 crowd and renewed interest in Britain thanks to McLaren's championship leader Lewis Hamilton, but the race's future beyond 2009 remained uncertain.

"It hasn't changed anything has it?," he told reporters at the suggestion that Hamilton, who finished third on Sunday for his ninth podium in a row, had made the race more secure.

"Maybe they will be able to wake up and think they can make things work and do something."

Ecclestone said the British Racing Drivers' Club (BRDC) needed to get moving on plans to revamp the pit and paddock complex.

While BRDC president Damon Hill, the 1996 world champion, said he hoped to get planning permission approved by the end of the year, Ecclestone suggested that would be too late.

"We have a contract that's been in place for five years, they've known for five years exactly what has to happen," he said. "By mid 2008 we've got to have the new buildings and everything put in place."

"I hope they've had a wake-up call and I hope they do something."

Hill said Sunday's race, with England midfielder David Beckham and wife Victoria in attendance, was positive for all.

"The story is well known that we want to develop Silverstone and there is a plan in place and I'm very positive that it will be a good ending to this saga and that Silverstone will keep pace with Formula One," he said.

Silverstone hosted the first championship grand prix in 1950 but is at risk with new races in Valencia, Singapore and Abu Dhabi due to be added to an already crowded calendar.