The Conservatives have gone ahead of Labour in the polls for the first time in more than two years.
An ICM survey for The Guardian put the Tories on 33 per cent, up one point from last month, while Labour fell by six points to 31 per cent.
Ukip moved ahead of the Liberal Democrats with ICM putting it on 15 per cent, up by four points on the poll in April. The Lib Dems were up by one point on 13 per cent.
Another poll published on Monday also gave the Conservatives a two-point lead. The survey for Lord Ashcroft, the party’s former deputy chairman, put the Tories on 34 per cent, Labour on 32, Ukip on 15 and the Lib Dems on nine.
The ICM poll found that 51 per cent of voters thought Labour leader Ed Miliband was doing a bad job, compared to 26 per cent who thought he was doing a good one. His overall rating of minus 25 percentage points is the worst score ICM has recorded for him to date.
Nick Clegg fared slightly better with 30 per cent saying he was doing well and 51 per cent thinking he was performing badly, for an overall rating of minus 21.
David Cameron’s approval rating was plus 2 points, with 44 per cent of voters saying he was doing a good job as Prime Minister, compared to 42 per cent who thought he was doing a bad job.
But George Osborne, whose approval rating hit minus 25 in 2012, did better than his boss with 41 per cent saying he was a good Chancellor, compared to 36 per cent who thought he was a bad one, for an overall score of plus 5.
Nigel Farage’s popularity is waning, according to the poll. His approval rating was plus 17 in May last year, but this month’s ICM poll putting him on minus 8.