Tony Blair is expected to set a date for his resignation as British prime minister when he makes an announcement about his future today.

Mr Blair, who notched up 10 years in power last week, is expected to stay as prime minister and Labour Party leader until a successor can take over at the end of June or early July.

Finance minister Gordon Brown, with whom Tony Blair has had a close but uneasy relationship, appears certain to win a seven-week Labour Party leadership contest. Mr Blair is "expected to make an announcement tomorrow on his future," a Labour Party source said yesterday, without giving details. Tony Blair is Labour's most successful leader, winning three national elections in a row. But his popularity has been hit by the war in Iraq and political scandals and he was forced by a Labour rebellion in September to say he would leave power within a year.

In elections last week, Mr Blair's Labour Party lost its position as the biggest party in the Scottish parliament to nationalists seeking independence from Britain.

In English local elections, the opposition Conservatives won some 40 per cent of the votes to Labour's 27 per cent.

One by one over recent weeks, potential heavyweight challengers for the leadership have said they will not challenge Mr Brown, long regarded as Tony Blair's heir.

That leaves two left-wing lawmakers - John McDonnell and Michael Meacher - as the only declared leadership contenders.

They have agreed that the one with the most support will press ahead with his challenge and the other will drop out.

But it is uncertain whether they will be able to win the backing of the 45 members of parliament needed to get on the leadership election ballot.

Conservative leader David Cameron mocked Tony Blair's team in parliament yesterday, calling it the "government of the living dead" and asking why Britain had to put up with seven weeks of paralysis while Labour chose a new leader.