Mr Robert Bourne, the Labour donor bidding for the Millennium Dome with Treasury Holdings, hopes to make a profit within three years, prompting criticism that the British government is selling the attraction at a knockdown price.

Mr Bourne, who with Treasury's Mr John Ronan and Mr Richard Barrett, has offered to pay £125 million sterling (#197 million) to turn the Dome into a high-technology business park, told the Financial Times yesterday he was confident of turning a profit within three years of operation. He hopes to profit from developing land around the Dome owned by English Partnerships.

The Opposition Conservative party said the admission was further evidence the government was undercharging Mr Bourne, who has paid £100,000 to Labour over three years.

Mr Peter Ainsworth, shadow culture secretary, said: "I've nothing against anyone making a profit, but this is a public asset and he should pay the appropriate price."

Mr Bourne said his Legacy consortium would be ready to sign a deal "very shortly". Legacy is to meet the government's competition team tomorrow to finalise issues. It is understood that the team will prepare a report for ministers on Friday before a meeting on Monday.

Legacy has guaranteed the government a significant share of the profits if it sells the Dome within 10 years.