Blair risks party's wrath by refusing to reveal his exit strategy

Tony Blair has flatly refused to bow to the mounting pressure from Labour MPs for him to set out the timetable under which he will stand down as Prime Minister.

He risked a new outbreak of Labour civil war by warning that his authority would drain away if he revealed his planned exit strategy. The scene is now set for a potentially bloody annual Labour conference in Manchester later this month.

Although Mr Blair is expected to leave Downing Street at some point next year, his refusal to state that publicly before or during the conference infuriated his internal critics last night. One opponent described his stance as "a declaration of war" on his own party.

In an interview in The Times today, Mr Blair said: "The difficulty is, if you start laying down timetables, then what you do is provoke another endless bout of speculation and the authority of the Prime Minister's position becomes difficult in those circumstances."

Defying his critics, he told them to "stop obsessing" about the leadership, warning that this led people to think the Government was paralysed and had run out of steam. He made clear his determination to bind his successor, almost certainly Gordon Brown, to a Blairite agenda. "I happen to believe passionately that it is New Labour or bust for us."

Calling for a wave of fresh ideas for the next phase of his New Labour project, he said: "The policies and ideas that represent that position will be different in 2007 from what they were in 1997."

Mr Blair insisted he had gone further than any sitting Prime Minister by spelling out his intentions - by saying in 2004 he would not stand for a fourth term, promising not to emulate Margaret Thatcher by going "on and on and on" and pledging to give his successor "ample time" to settle in before the election. He said: "Now at some point, people have got to accept that as a reasonable proposition and let me get on with the job."

He said there were three groups of critics worried about his stance. To those worried that Labour was trailing the Tories in the opinion polls, he insisted his party was in a much stronger position than the Tories in 1990 when Baron-ess Thatcher was forced out. To those concerned he would not stand down voluntarily, he had already made clear he would not go "on and on and on". Finally, to critics who wanted to change the direction of New Labour, he said he wanted a proper debate about the party's future.

He pleaded with Labour to trust him to "do his best for the party and country and depart in a stable, sensible and orderly way". But he declined to confirm in the interview that this month's conference would be his last as leader. "I really think it is absurd for the people who say we must stop this continual speculation about the leadership to continue to speculate about it," he said. Mr Blair's uncompromising message to his party threatened to swell the ranks of the Labour MPs demanding he set out a firm departure timetable by the conference. They extend to normally loyal MPs.

One critic said: "This will be seen as a declaration of war on the Labour Party. People have had enough of the Prime Minister saying he wants a 'stable and orderly transition' but then doing nothing to start that process."

But a Blair aide insisted: "Nothing could be further from the truth. This is not a declaration of war. He is making clear his position in more detail than ever before, and is calling for a clear and open debate about the policy ideas and framework for the next generation of New Labour in office."