The costs for London's Olympic Games has reached £9.3bn
Three 2012 Olympic venues in London are being evaluated by accountants to see whether they will deliver value for money, the government has confirmed.
The Department for Culture, Media and Sport (DCMS) confirmed that KPMG are reviewing plans for the equestrian, shooting and basketball venues.
Equestrian events will be at Greenwich Park, shooting will be in Woolwich and the Olympic Park will host basketball.
The DCMS said reviews were part of a bigger process to ensure viable Games.
The 23,000-seater stadium for equestrian events and the 7,500-seater shooting facilities at the Royal Artillery Barracks in Woolwich are due to be dismantled after the Games.
The 12,000-seater basketball arena to be built in the main Olympic Park, where only the qualifying rounds will be held, has also been marked for relocation.
A DCMS spokesman said: "This is one of a number of reviews of Olympic venues to ensure they are being delivered as efficiently as possible and meet both Games and long-term legacy requirements.
"It is part of the ODA's (Olympic Delivery Authority) role to continually seek cost savings in order to achieve best value for money in delivering its programme, so such reviews will continue to be undertaken in order to validate delivery plans."
Since London won the race to host the 2012 Games costs have risen to £9.3bn - nearly four times the estimate stated in the bid in 2005.
The Olympic authorities have also had to change venues for fencing, canoeing and the kayak slalom events.
The costs of the three proposed venues under review have not yet been revealed.