The Conservative leader said the success had been a "vote of positive confidence" for his party, which won control of 12 authorities including important northern councils such as Bury and North Tyneside.

He set off to congratulate some of the winning councillors yesterday as Gordon Brown vowed to "learn the lessons" of a disastrous defeat which saw Labour lose more than 300 seats and eight councils, far worse than many had feared.

Labour also lost control of five Welsh authorities, with the Conservatives gaining control in the Vale of Glamorgan.

Mr Brown blamed economic conditions for the defeat, which looked set to push Labour one point behind the Liberal Democrats in the share of the vote nationally on 24 per cent, Labour's worst set of council election results in four decades. The Tories looked set to secure 44 per cent of the vote.

Liberal Democrat leader Nick Clegg saw his party's vote share fall from last year, but gained 30 council seats and also took control of Sheffield, Hull, St Albans and Burnley.

Mr Cameron said it was a "big moment" for his party, adding: "I think these results are not just a vote against Gordon Brown and his Government. I think they are a vote of positive confidence in the Conservative Party."

In Downing Street, Mr Brown blamed the "testing" economic conditions for the Labour's poor performance which drew comparisons with the drubbing John Major's Tories suffered in 1995, two years before their landslide General Election defeat, as Labour backbenchers gave him six months to improve performance.

Mr Clegg said the Liberal Democrats had broken the grip of Labour in the North and made great advances in the South. "We have confounded the critics and the sceptics and gone forwards rather than backwards."