Taxpayers have had to pay out more than £30m to maintain the Millennium Dome since it closed at the end of 2000, it has emerged.
Development of the site should finish in 2007
Lord Rooker, a minister in the Office of the Deputy Prime Minister, said expenditure would continue at a reduced rate once work on a music arena began.
When construction of the proposed new development is completed, hopefully in 2007, the costs should cease, he said.
But Tory Lady Seccombe denounced the figure as "appalling".
Lord Rooker said all costs would be recovered by the current owners, English Partnerships, from the proceeds of sale.
He said the amounts involved were seed corn compared to the "massive" benefits that would accrue to the area.
Since the Dome closed as the Millennium Experience it has stayed mainly empty.