TONY BLAIR kept alive his proposals to detain terrorist suspects for 90 days last night after winning strong support from Labour MPs and promising that the plan would have to come back to Parliament in a year for another vote.

As a Populus poll for The Times showed overwhelming support for the 90-day option, Mr Blair was told by many MPs at a packed meeting of the parliamentary party that they wanted the chance to vote for it. He proposed a “sunset clause”, under which the proposal would lapse after 12 months and have to be re-endorsed by Parliament. The move would mean that the police and security services would have to show that they had used the provisions responsibly and that it had not led to a breach of civil liberties.

At the same time a senior Labour backbencher, Janet Anderson, tabled an amendment reducing the detention period to 60 days. But this is intended only as a fallback position if the Government should be defeated on 90 days. Ms Anderson will back the 90-day plus sunset clause amendment. Only if it fails will she move her 60-day plan to avoid the passage of another amendment proposing 28 days, which has support in all parties.

Speaking outside the Home Office in London, Charles Clarke, the Home Secretary, said he was confident that the amended Bill would be voted through by MPs tomorrow.

He said that he had decided not to give further ground after the “very strong support” given to the plans at last night’s meeting. Furthermore, he said that he had got a very strong feeling throughout the day that “this was the right thing to do”.

Mr Clarke also said that there was now real disquiet among Tory backbenchers over their party’s opposition to the move. The Conservatives have said that they cannot move beyond the proposal for a detention period of 28 days.

Mr Blair believes that he is in a strong position because of the strength of public support for the 90-day plan. Today’s Populus poll for The Times found that 64 per cent of people backed the 90-day plan with only 32 per cent against. This includes a majority of every social, age and party group, including 71 per cent of Labour voters, and even 52 per cent of Liberal Democrats.

Last night’s move came after a fighting performance from Mr Blair. Even known opponents said that he had given an impressive display. But with Mr Blair hit by the David Blunkett resignation and growing opposition among Labour MPs to his reforms of education and health, the Populus poll had less palatable news for the Prime Minister. It found that 59 per cent of voters now believe that his authority is ebbing away.

Labour still, however, remains well ahead of the Tories in voting intentions. It is now on 40 per cent, unchanged from a month ago, with the Tories on 32 per cent, up two points. The Liberal Democrats are down two points at 19 per cent, with others on 9 per cent. But voters are divided on whether Mr Blair should be replaced soon by Gordon Brown. A majority of Labour voters do not want such an early change.

Last night, he told the Parliamentary Labour Party that he was trying to build a platform for a fourth Labour election victory with his reforms on health, education, pensions, welfare and energy policy.

Mr Blair said yesterday: “This is a tough and critical moment. Just because we were re-elected five months ago on a manifesto of radical reform does not make it any less turbulent to see it through.”

Dominic Grieve, the Shadow Attorney-General, said that he had told the Home Secretary that the 90-day period was totally unacceptable to the Conservatives. Michael Howard, the Conservative leader, said: “We have to do what we believe is right. We have made it absolutely clear. We think 28 days is the absolute limit of what should be permitted.”

• Populus interviewed a random sample of 1,512 adults aged over 18 by telephone between November 4 and 6. Interviews were conducted across the country and the results have been weighted to be representative. Populus is a member of the British Polling Council and abides by its rules. For more details see www.populuslimited.com.

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