The first in a new monthly series of polls for The Times conducted by Populus shows that Mr Blair is now being damaged politically, particularly among women, by his tough stand and close alliance with President Bush.

The Times/Populus poll, undertaken between last Friday and Sunday, shows how much Mr Blair still has to do to win over voters and how public attitudes are closely linked to his ability to win support for a second United Nations resolution. This further underlines the importance to Mr Blair of this Friday’s report to the Security Council by Hans Blix, the chief weapons inspector.

The public believes that President Saddam Hussein is a threat to Britain and has weapons of mass destruction. But they do not think that the case for war has been made.

Nearly nine out of ten voters think the UN weapons inspectors should be given more time to establish whether Iraq is hiding weapons of mass destruction, as France, Germany and Russia have urged. Meanwhile, just a third think that Britain and America have so far put forward a convincing case for military action against Iraq.

More than half of the public says their view of Mr Blair has changed because of Iraq, a third less favourably.

Support for Labour has slipped two points over the past month to 35 per cent. Apart from the fuel protest month of September 2000, the last time Labour support was this low was in 1992.

The Tories are now virtually level-pegging, at 34 per cent, up two points over the past month and matching the party’s highest level since the last general election. The Liberal Democrats are unchanged over the month on 25 per cent, the ninth month running that the party has been at or above 20 per cent.

The shift in voting intentions over the past month primarily reflect changes in party supporters’ likelihood to vote. Populus bases its polls on those who are most certain to vote, and there has been a sharp drop over the past month in the likelihood of Labour voters turning out. Disillusion over Iraq is undoubtedly a major influence.

This trend is worrying for Mr Blair ahead of local elections in much of Britain outside London in early May. Labour leaders fear that their traditional supporters will abstain in large numbers. The poll underlines his political vulnerability not just over Iraq but also more generally following recent controveries over university funding, the health service and House of Lords reform.

However, contrary to the criticism of many Labour MPs and party activists ahead of the big anti-war demonstration in London this Saturday, the poll shows that Labour supporters are less hostile to war than supporters of other parties. Nearly two fifths of Labour voters are more supportive of Mr Blair because of Iraq, though a fifth are less supportive. There is a marked contrast with Lib Dem supporters who are the least inclined to regard the Iraqi leader as a threat and are most opposed to military action.

Tory support is firm partly because of the party’s relatively high support among older people, who are more likely to vote. Moreover, Iain Duncan Smith’s strong support for the US over Iraq has impressed Tory voters, three in ten of whom are now more supportive of him.

But this strengthening of support for Mr Duncan Smith among core Tory voters is matched by continued scepticism among the public as a whole. Slightly more voters are less supportive of him because of Iraq. So far the Tories have consolidated their base support rather than won over many converts.

The Times/Populus poll asked the public to rate the party leaders on a one to ten scale. The Liberal Democrats’ Charles Kennedy came top with a mean score of 5.20, followed by Mr Blair on 5.02 and Mr Duncan Smith on 4.00. Mr Kennedy is not far behind Mr Duncan Smith among Tory voters, while Mr Blair still does best among his own party’s supporters.

The poll brings out the complicated public attitudes to Iraq. By an overwhelming margin, voters accept the British and US case against Saddam Hussein over Iraq’s possession of weapons of mass destruction, its concealment of them and its help for international terrorists. Nearly half the public believes that Iraq has links with al-Qaeda.

But barely a third of voters think that Britain and America have put forward a convincing case for military action against Iraq, with nearly three fifths disagreeing. This is linked with support for giving the UN inspectors more time to establish whether Iraq is hiding weapons.

The poll shows a marked gender gap, especially in attitudes towards Mr Blair. Women are much more likely than men to regard him as “George Bush’s poodle” and as wrong to support military action in defiance of public opinion. But, overall, fewer people now regard the Prime Minister as “George Bush’s poodle” than last October.

Although more than a half of voters say their view of Mr Blair has been changed by Iraq, three fifths say that Iraq has made no difference to how they see Mr Duncan Smith and Mr Kennedy.

Populus interviewed a random sample of 1,004 adults aged 18-plus between February 7 and 9. Interviews were conducted across the country by telephone and the results have been weighted to be representative of all adults.

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