The cost of building the London 2012 Olympic stadium has increased by 216 million pounds ($440 million) from the original figure in the bid document, the Olympic Delivery Authority (ODA) said.

New ODA chairman John Armitt, the man in charge of delivering the venues and infrastructure of the Games, told members of the cross-party London Assembly on Wednesday that the new figure was 496 million pounds, a rise of 77 percent.

In March this year the Government more than doubled the budget for preparing and building the Games venues to 9.3 billion pounds, sparking fears of spiraling costs.

Olympic chiefs maintain that a large chunk of the revised budget is for long-term regeneration of what is a neglected part of east London.

Armitt said the increased figure for the Olympic Stadium was "in line with budget" and not a dramatic escalation of costs.

"To suggest that the costs have doubled from the bid book represents a grossly misleading figure for the public," he said. "This figure represents a 2012 outturn cost which includes inflation, VAT, legacy conversion and earthworks.

"The bid figure was a 2004 figure which all the bidding cities were asked to give. Insofar as a comparison can be made with the bid book the figures are broadly in line."

"The bid book was the bid book, but the reality is we are where we are, and we have to work within the budget approved by the government."

Armitt said the first designs for the 80,000-seat stadium would be unveiled later this month, although it is still to be decided what the post-Games use of the scaled down 25,000-seater stadium, will be.

Armitt also said it was too early to give a final cost figure for the aquatics centre designed by Zaha Hadid. London's bid book quoted 75 million pounds.

The cost for the other major new venue, the swimming and diving center, is also expected to be much higher than originally planned. While the bid book put the figure at 75 million pounds, the final cost is now expected to exceed 150 million pounds.

"I'm not sure where we are going to finish up," he said. "The important thing is that it does the job that is required."

The ODA announced this week that the canoe slalom venue north of London may have to be moved to an alternative location after contamination was discovered. (1 pound = 2.037 dollars)