The Northern Ireland secretary will play a central role in planning the party's next general election campaign, working with Chancellor Gordon Brown.

Prime Minister Tony Blair said Mr Brown would chair the party's election strategy committee, which oversees the campaign.

Mr Mandelson will head the election planning committee, which takes responsibility for the day-to-day running of the campaign.

The two men played the same roles for Labour's 1997 election campaign, but have been bitter rivals in the past.

Chancellor Gordon Brown will be in charge of election strategy

Cabinet Office Minister Ian McCartney will have a co-ordinating role, as he also did two years ago.

A Labour spokesman said Mr McCartney would "rally the party in the country", getting "out and about motivating members and supporters as Labour seeks to maximise its vote".

Mr McCartney is close to Deputy Prime Minister John Prescott. The trio of appointments will be seen as fulfilling a balancing act between the competing camps at Labour's highest levels.

The Paisley South MP Douglas Alexander will act as Mr Mandelson's deputy. It is also expected he will stand in for Mr Mandelson when Northern Ireland duties keep the secretary of state away from Labour's Millbank headquarters.

Swift rehabilitation

Mr Mandelson's return to the top of the Millbank machine completes his swift rehabilitation to Labour's top ranks after he was forced to resign in disgrace from the cabinet last Christmas over a secret loan from the then-paymaster general, Geoffrey Robinson.

The Hartlepool MP, who was secretary of state for trade and industry at the time, had failed to disclose the loan to the prime minister or his senior civil servants, despite the fact that his own department was overseeing investigation in Mr Robinson's business affairs.

But Mr Mandelson, one of Mr Blair's closest confidants, was brought back into the cabinet after just 10 months on the backbenches.

His new job will disappoint his many enemies within Labour, both at backbench and cabinet level, whose mistrust of Mr Mandelson goes back to when he first started spindoctoring for for the party in the mid-1980s as its director of communications.

The appointments to the election team may also be seen as a rebuff to leader of the House of Commons Margaret Beckett, who was in charge of the European elections when Labour was beaten by the Tories.