A former Metropolitan Police chief says he was aware of claims pornographic material was found on a computer in the parliamentary office of MP Damian Green.

Sir Paul Stephenson said he was briefed about the allegation but it "wasn’t relevant to the criminal inquiry" into Home Office leaks, which began in October 2008.

The Ashford MP has emphatically denied the allegation and says it is a smear. The claims were initially made by Bob Quicke, the Met Police chief who led the leak inquiry in 2008.

Sir Paul, referring to the pornography allegations, said: “I regret it’s in the public domain. There was no criminality involved, there were no victims, there was no vulnerability and it was not a matter of extraordinary public interest.”

Mr Green, who is facing a cabinet inquiry into claims he denies about inappropriate conduct, said: "I reiterate that no allegations about the presence of improper material on my parliamentary computers have ever been put to me or to the parliamentary authorities by the police. I can only assume that they are being made now, nine years later, for ulterior motives."

Mr Green’s home and office were searched as part of that probe and he was briefly arrested in November that year, but no action was taken against the MP.

Sir Paul added it was not Scotland Yard’s role to “police the workplace”.

An inquiry investigating whether the MP breached the cabinet’s code of conduct after claims of inappropriate behaviour made by a female journalist is continuing.