The centre will host swimming, diving and water polo events
The London 2012 Olympics aquatics centre will cost more than three times as much as originally estimated, it has been confirmed.
The east London centre will cost £242m, not the £75m quoted in London's winning bid, despite a reduction in its size.
The Olympic Delivery Authority (ODA) said construction inflation and VAT had raised the price. Overall construction costs remained within budget, it added.
The ODA also said that Team Stadium would build the £496m Olympic Stadium.
The British construction team previously built Arsenal's Emirates Stadium in north London, as well as the Telstra Stadium in Sydney.
Another British firm, Balfour Beatty, will build the aquatic centre at the Olympic park by 2011, two years later than originally planned.
The 17,500-seat venue will host swimming, diving and water polo events during the 2012 games.
Its two 50-metre swimming pools and diving pool will be made available for public use afterwards.
An ODA spokesman said the centre's original estimated cost of £75m was based on 2004 prices.
The "full lifetime budget" of £242m reflected additional VAT costs, construction inflation and the cost of converting the site into a public building after 2012, he said.
"There have also been big changes to the site since the first plan," he said.
"Some of the land available for the aquatic centre got smaller, so the design had to become more compact."
Its roof will now be 11,200 square feet, which is under a third of the original 35,000 square feet.
A giant bridge to the aquatic centre will cost a further £61m, the ODA added.
It said the cost of building the centre and stadium were within its total construction budget of £6.09bn.
Olympics minister Tessa Jowell said: "The aquatics centre and stadium will be the showcase venues for 2012 and I am delighted that British companies will build them."