TONY BLAIR has defied his critics by refusing point-blank to name a date for his departure and insisting that he has no intention of saying more about his future either before or during the Labour Party conference.

He has used an interview with The Times to try to head off growing demands for him to set out a broad timetable for his exit, saying that to do so would trigger another endless bout of speculation and damage his authority.

He told his party to “stop obsessing” about the leadership and get on with the business of government. If it kept talking about the leadership, people would think the Government was paralysed or had run out of steam, he claimed.

Mr Blair said that the MPs who “carried on and on” about his leadership were really doing so because they wanted a change of direction away from new Labour.

But in words clearly designed to reassure opponents and many supporters he said that, unlike Margaret Thatcher, he would not go “on and on and on” and promised again to give “ample time” for his successor to bed in.

By announcing in advance that he would not be fighting the next election, and then guaranteeing time for his successor, he had done more than any other prime minister in such a situation, and reasonable people would accept he had done enough, he said.

It was Mr Blair’s first interview since his summer holiday, during which internal party opposition to him grew over the Lebanon war.

With Labour MPs, including loyalists, demanding a timescale for his departure, Mr Blair’s refusal to give ground to the clamour will mean a difficult month for him. One senior Brownite MP told The Times last night that Mr Blair’s stance “would not wash” and that he would be pressed to go further. Mr Blair speaks at the TUC conference on September 12 with a potentially critical Labour conference opening on September 24.

He has effectively dared his critics to move against him, while trying to assure the main body of the party that it can trust him to do the right thing. He promised to “do his best for party and country and depart in a stable, sensible and orderly way”. But in the meantime he intended to get on with the job of being Prime Minister and governing the country.

There have been threats that MPs will start collecting signatures demanding a leaving date as a way of putting pressure on him before the conference. His attitude yesterday suggests that he believes he can face them down, even though nothing he said countered the increasingly strong view at Westminster that he will go in 2007.

Many times during a 50-minute interview at Chequers Mr Blair declined to say whether the coming conference would be his last as leader, the signal that many MPs and ministers have been seeking. “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. I’m not the one who keeps raising this issue. I have done what no other prime minister has done before me. I’ve said I’m not going to go on and on and on, and said I’ll leave ample time for my successor. Now at some point I think people have to accept that as a reasonable proposition and let me get on with the job.”

Asked to state categorically whether he would say more to defuse the issue before or at the conference he said that he believed he had said all he could. He could understand if people thought he was going on and on or not allowing ample time for his successor. But he was doing neither.

“I think if it is speculation that people are worried about, there is a simple answer — stop speculating. If what they are really worried about is timing I think most of you can look at at what I have said and draw conclusions about that,” he said. Mr Blair’s words could reassure some supporters who believe that he has given enough assurance that he knows his time is limited.

Martin Linton, a Blair loyalist, said last night: “I've always thought that he’s said he will give his successor ample time. There’s no need for us to spend all our time speculating about when that might be because he’s in the middle of a lot of things.”

In a separate interview Mr Blair has set out plans for state intervention to prevent potentially problem babies becoming problem teenagers of the future. He said teenage mothers could be forced to accept state help before their children were born as part of a clampdown on antisocial behaviour.

“If we are not prepared to predict and intervene far more early, then there are children that are going to grow up in families that we know perfectly well are completely dysfunctional, and the kids a few years down the line are going to be a menace to society and actually a threat to themselves,” he said.

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