Tory rivals tried to trap Cameron over cocaine

Stunned Conservatives looked on as Shadow Minister David Ruffley, 44, shouted at Tory backbencher Mark Pritchard, 40, that it would be 'madness' to put Mr Cameron on the spot over the issue.

The row came after fresh details emerged at Westminster of a dirty tricks plot against Mr Cameron, during his leadership campaign last year.

Two other prominent frontbench Tories were involved in attempts to show that Mr Cameron and one of his closest aides were involved with cocaine.

One MP is said to have used his wife to ensure that Mr Cameron was challenged over drugs at a meeting with Conservative MPs' spouses.

The disclosures follow The Mail on Sunday's revelation last week that Mr Cameron was nearly expelled from Eton after admitting smoking cannabis as a 15-year-old and continued to use the drug at Oxford.

The showdown between Shadow Welfare Reform Minister Mr Ruffley and Right-wing Mr Pritchard followed a secret meeting of supporters of Mr Cameron's chief leadership rival, David Davis, amid intense speculation about drug-taking in Mr Cameron's circle.

At the meeting, not attended by Mr Davis, Mr Pritchard reportedly said: 'I am going to ask the candidates if they have taken Class A drugs and I'll make sure Cameron answers.'

Later in the day, Mr Cameron and fellow candidates Mr Davis and Kenneth Clarke were questioned by Tory MPs at separate sessions held by the Thatcherite Conservative'92 Group.

Mr Pritchard asked a bemused Mr Clarke if he had taken Class A drugs and received a firm denial.

But before Mr Cameron entered the room, Mr Ruffley, also supporting Mr Davis, called Mr Pritchard out to the corridor.

According to one informed account, the two shouted and swore at each other as Mr Ruffley pinned Mr Pritchard against a wall.

Ruffley: 'It would be madness for you to try and embarrass Cameron over cocaine. It is crude and will backfire.'

Pritchard: 'What's it got to do with you? I've got a right to ask him whatever I like.'

Ruffley: 'But it will damage not just Cameron but David Davis as well because everyone knows you are one of his supporters.'

Pritchard: 'I've ve asked Clarke. It will look worse if I don't ask Cameron.'

Ruffley: 'All you will do is create headlines saying, 'Tories at war over drugs.'

Pritchard: 'Who has given you the authority to do this?'

Ruffley: 'I am telling you not to do it because it's wrong.'

Mr Cameron's aides had been tipped off and prepared a reply. But in the event, Mr Pritchard did not challenge him.

Mr Ruffley and Mr Pritchard declined to comment last night.

David Cameron: The Rise Of The New Conservatives is to be serialised exclusively in The Mail on Sunday next month.