A new poll has put the Conservatives 10 points ahead of Labour, their biggest lead since John Major's 1992 election win.

The Ipsos/MORI poll in the Sun on Monday put the Tories on 41 per cent, Labour on 31 points and the Liberal Democrats on 18 per cent.

David Cameron's party are up one point on last month, while Labour are down one and the Lib Dems down three.

The dramatic turnaround in Tory fortunes under Cameron is illustrated by the fact that last November, the month before his modernising leadership began, the party was 10 per cent behind Labour.

As Tony Blair battles with problems ranging from law and order to the furore over his deputy, John Prescott, approval ratings for his premiership have also plunged to minus 41 per cent.

Two thirds of voters now say they are dissatisfied with the prime minister, while only 26 per cent are happy.

The six-point fall in his approval among the public as a whole is even greater among Labour voters, with ratings among his usual supporters having halved since March.

Lib Dem leader Sir Menzies Campbell will also be disappointed with the findings which show his party struggling to cope with the Conservative revival under Cameron.

The Tory leader will seek to keep his momentum going this week as he marks six months in the job.

He will use a speech on Tuesday to praise the public sector and attack home secretary John Reid for criticising civil servants.

Meanwhile, more than 650 senior City figures were on Monday set to attend a Conservative event in London aimed at encouraging business backing.

Top executives, brokers and fund managers were among those invited to the 'City Circle' reception.

And shadow chancellor George Osborne said business and economic leaders are increasingly viewing the Tories as a government of the future.

"We've been in opposition and the City were interested in the government and I understand that," he said.

"The City is interested in where the power and the future lies. What's interesting is the City are now very interested in us."