TONY Blair yesterday tried to head off backbench plotting to force him out of Downing Street by pledging for the first time to quit early - but without setting a firm date.

At a hastily-arranged Press conference, the Prime Minister signalled that he no longer intended to serve a full third term.

Instead, Mr Blair promised to allow "whoever succeeds me to have the time to bed in and lead the policies of change up to the General Election".

The new phrasing of his plans was seen as increasing the chances of a handover to Gordon Brown - almost certainly his successor - some time next year.

It is widely believed that the new prime minister would need at least 18 months to make his mark, which could imply that Mr Brown would be in place by Labour's autumn conference next year.

Later, Mr Blair ducked the chance to confirm he would still be in Downing Street at next year's local elections.

The change of tack was designed to win breathing space after a weekend of increasingly feverish claims that backbenchers are calling for a firm timetable for his departure.

About 50 MPs are rumoured to be willing to sign a letter setting a July deadline for that timetable to be made clear to Mr Brown and other senior Labour figures.

But Mr Blair, who again promised to secure "a stable and orderly transition", declined to say whether he had told his Chancellor when he intended to go.

And his attempts to put recent crises behind him were undermined by the revelation that at least 150, rather than 90, serious offenders were among the 1,000 wrongly-freed foreign criminals.

John Reid, who last week replaced Charles Clarke as Home Secretary, said the figure would be even higher if armed robbers were included.

Last night, at a packed meeting of the parliamentary party, Mr Blair faced demands from his MPs to set out in more detail what he meant by giving his successor "time".

After the meeting, one backbencher said the Prime Minister would be expected to make clear his intentions by September's party conference.

But another said: "MPs were happy with what the Prime Minister said. It has taken the wind out of the sails of those wanting blood now."

Tory leader David Cameron told the first of his regular news conferences: "This is a state of civil war at the highest levels of Government."

At his Press conference, Mr Blair refused to give a timetable for his departure, insisting it would "paralyse the proper working of Government".

Rounding on the plotters, he said some of them wanted not to remove him but to "radically change the direction of policy and, not to renew Labour, but to reverse it".

Mr Blair will be hoping the promise of allowing his successor time will persuade his more rebellious MPs to step back from mounting a leadership challenge this year.

That scenario is seen as unlikely while Mr Brown - who fears inheriting a divided and demoralised party - steers clear of supporting any coup attempt.

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