But he pleaded innocent to a separate charge of conspiracy to pervert the course of justice.

The one-time Chief Secretary to the Treasury and potential candidate for the Tory leadership appeared at the Old Bailey for a plea and directions hearing alongside his former associate Said Ayas.

A trial will now be held on the charge of conspiracy to pervert the course of justice later in the year.

The proceedings follow the failed libel case which Mr Aitken entered into against The Guardian and ITV's World in Action programme.

In 1995 Mr Aitken resigned from John Major's Cabinet to defend himself from the accusations.

Once out of the Cabinet, Mr Aitken sued the media companies.

His case collapsed in 1997. Charges were then brought against Mr Aitken in May 1998 - the only former Cabinet minister to be faced with serious criminal charges in living memory.

Mr Aitken's wife Lolicia left him after his case collapsed.

In August 1998 the Crown Prosecution Service decided against bringing charges of conspiracy to pervert the course of justice against their teenage daughter Victoria.