London 2012: Mps Demand Answers From Jowell on Overspend

The culture secretary Tessa Jowell faces another grilling from MPs alarmed at the impact that overspending on the London 2012 Olympics could have on charities.

Questions have been raised by MPs following Jowell's appearance last week before the culture, media and sport select committee, in which she admitted the games budget had soared by at least £900m with further rises inevitable.

The committee is likely to publish its report - expected to be highly critical of the uncertainty surrounding the budget - before Christmas. John Whittingdale, Conservative chairman of the all-party committee, demanded: "Where is the extra £900m coming from? Under the government's memorandum of understanding any additional costs have to be covered by the London council tax or the lottery. In my view the national lottery is already under severe strain. It is difficult to see how any more can be taken from it."

The lottery is providing £1.5bn, with £750m from Olympic draws and scratchcards. A further £340m is being taken from Sport England's lottery war chest, with the remaining £410m diverted from arts, heritage and other good causes after 2009.

The government said it had made no secret of the fact it might be necessary to ask for more money from the lottery.

"Holding the games will be of benefit to the country as a whole. The ambitions of the Olympics fit into the overall philosophy of the lottery, leaving a sporting legacy and regeneration," the spokesman added. Whittingdale said Jowell's evidence begged more questions. "We have sent her a whole series of questions on detailed costings," he said.

A Department of Culture spokesman said: "We are always committed to keeping the committee informed. We were as transparent as possible last week and will respond to further questions as fully as we can."

Jowell told the hearing she was willing to provide additional written evidence.

Although the committee succeeded in prising out fresh details of the budget for the Olympic Park, which now stands at £3.3bn but does not include any of the regeneration of the Lower Lea Valley in east London, Whittingdale said MPs still had many concerns.