The council is considering closing the whole site

The Crystal Palace National Athletics Stadium returns to Bromley Council's ownership next year.

The council says it cannot afford to keep it open, nor the �30m needed to bring the 40-year-old site up to date.

But the mayor says an �18.5m deal has been struck with the government, Sport England and businesses.

"The future for Crystal Palace looks a lot brighter now than it has done for many years," he said.

The site's lease is currently held by Sport England, but runs out on 31 March when ownership will return to Bromley Council.

The complex includes London's only 50 metre swimming pool

It is considering shutting either the stadium, or the whole site - which includes London's only 50-metre swimming pool.

It would mean the stadium could not host the annual London athletics Grand Prix and could be a blow to London's 2012 Olympic bid.

Mr Livingstone said both Sport England and the government had given "the strongest assurances" they would provide �10m towards a new indoor sports centre.

The London Development Agency has been asked for �2m, Sport England has offered �1.5m for the outdoor stadium and private sector backing is being sought.

"If Bromley agrees to provide �5m from its more than �40m reserves, together from what can also be leveraged in from the private sector, London will continue to host international athletics over the course of our Olympic bid," said Mr Livingstone.

But Brian Turpin, the council's head of marketing, was more sceptical about whether the stadium's future had been secured.

He said it was not clear which money was guaranteed - including the �5m the council is being urged to apply for from the Heritage Lottery Fund.

"It is still a shortfall on the �30m required and we have some concerns about the figures," he added.