The government's ownership of the New Millennium Experience Company is represented by a single share in Mr Mandelson's name.

But following the minister's resignation from the government, his future involvement in the Millennium Dome is unclear.

An NMEC spokesman told reporters: "We have not heard from the Government yet about what is happening."

Assurances

Mr Mandelson has held the single share since 26 June 1997.

He saw the huge structure in Greenwich, south London, as a chance to emulate his grandfather, former Labour Cabinet Minister Herbert Morrison, who masterminded the 1951 Festival of Britain celebrations.

He was at pains to rule out the possibility of a conflict of interest between his Dome role and his new position of Trade and Industry Secretary.

Peter Mandelson quit over a loan from the Paymaster General

He made assurances over British Airway's sponsorship of the Dome. At the time the DTI was due to rule on the possible threat to competitiveness of British Airway's proposed link-up with American Airlines.

The NMEC said: "Peter Mandelson, as the shareholder, played no part in negotiating or procuring sponsorship contracts for the Dome.

"All contracts were handled by the NMEC in-house sponsorship team."

Criticism

Conservatives last week criticised an announcement that Granada had won a lucrative catering contract at the Dome.

They pointed out that the award had gone to a company whose chairman, Gerry Robinson, had prominently campaigned for Labour in the 1997 General Election.

The decision had shown "the conflict" between Mr Mandelson's twin roles as Trade and Industry Secretary and Dome supremo, said Conservative culture media and sport spokesman Richard Spring.

£30m publicity campaign

The NMEC is close to hitting the £150m sponsorship target it needs for the Dome which will open with a glittering party on 31 December, 1999.

The massive Dome - big enough to contain two Wembley Stadiums and 13 Royal Albert Halls - is expected to attract at least 12m visitors throughout the whole of 2000.