Gordon Brown’s leadership rating has fallen to its lowest level yet, with a third of voters regarding him as worse than Tony Blair, a poll for The Times finds today.

The Prime Minister has also presided over a sharp fall in confidence in the economy as he enters a crucial three weeks of campaigning for the London and local elections.

The Populus survey will reinforce the gloom among Labour MPs, with Mr Brown facing a sizeable backbench revolt over his decision as Chancellor to abolish the lower 10p band of income tax. Some ministers already accept that concessions will have to be made to avoid a defeat on a Budget measure.

In the poll, undertaken over the weekend, the Tories have risen two points since a month ago to 39 per cent and Labour has slipped one point to 33 per cent. The Liberal Democrats are down two points at 17 per cent. These are within one point of the average ratings this year. The poll also finds that 31 per cent of voters now regard Mr Brown as worse than Tony Blair.Support for Labour is now following a similar path to that of the doomed Conservative Government at the same point in the mid-1990s. The Tories have been in the lead for all but three months of the past two years, although they are well below the level of the Labour Opposition in the 1990s. The number of voters thinking that the economy will fare well over the next year has fallen by a quarter to 39 per cent since last September. This is half the level of three years ago and the lowest in the five years that the question has been asked. The number thinking that the country will do badly has risen from 45 to 59 per cent in seven months.

More than two thirds of voters (70 per cent) say that Britain is heading in the wrong direction. Mr Brown’s leader rating (on a 0 to 10 index) is down again, to 4.50 from 4.59 a month ago. This is lower than all but one month of Mr Blair’s leadership. Mr Brown’s rating among Labour voters has fallen sharply from 6.72 to 6.26.

The Prime Minister will play a personal role over the coming two weeks of parliamentary recess in trying to defuse the backbench rebellion. The Government appeared to accept for the first time yesterday that it would have to make changes in order to keep its 2007 Budget intact.

There is no question of going back on the abolition of the 10p rate, but ministers believe that moves will have to be made to appease MPs and the lower-paid workers, many of them part of Labour’s core vote, who have been hit. Downing Street officials accepted that before the Pre-Budget Report next autumn the Government would have to consider complaints that low-income single people and childless couples would be worse off. Mr Brown’s official spokesman continued to rule out a significant reversal on the ground that the change was part of a “coherent package” that allowed him to cut the basic rate of income tax by 2p a year ago and that losers were compensated elsewhere by rises in child benefit and tax credits.

David Cameron remains the most highly rated of the three leaders, at 4.96, although this is down from 5.23 previously, and is back to the level of a year ago. Despite all the recent controversy involving him, Nick Clegg’s rating has risen slightly this month from 4.16 to 4.27, but this is still only just above the low point touched by Sir Menzies Campbell in May last year.

After Mr Brown’s brief honeymoon last summer, voters have become much more critical. Whereas last September 21 per cent believed that he had performed better than expected, now just 5 per cent do. Over the same period the number saying that he has done worse than expected has risen from 6 to 36 per cent. A mere 3 per cent think that Mr Brown had made a real difference to Britain; 33 per cent only a little difference; and 62 per cent no difference at all.

The proportion regarding Labour as competent and capable has fallen from 56 to 37 per cent since last September and the Conservative rating has risen from 39 to 45 per cent.

— Populus interviewed a random sample of 1,502 adults aged over 18 by telephone between April 4 and 6. Interviews were conducted across the country and the results have been weighted to be representative of all adults. For more details see www.populus.co.uk

— Labour MPs are embarrassed over their failure to spot earlier the pitfalls of the abolition of the 10p starting rate of tax. Most of the MPs who are now castigating Gordon Brown happily backed him in the lobbies last year when they knew that it was his last Budget. Most of the 27 MPs who backed Greg Pope’s Commons motion calling for a rethink had voted in favour of the measure after it was announced in the 2007 Budget. They were warned of the consequences. All newspapers in their lead stories after the Budget made plain that the cut in the basic rate of tax to 20p would be balanced by the scrapping of the 10p rate.

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