A former Metropolitan police commissioner was aware of allegations that pornography had been found on Damian Green's office computer during a police inquiry, he has said.
Sir Paul Stephenson, Britain's most senior police officer between 2009 and 2011, said he was briefed about the claims but regarded them as a "side issue" and regretted that they were in the public domain.
The disclosure came amid questions about the political future of Green, Theresa May's de facto deputy, who is already facing an allegation of sexual harassment from former Conservative activist Kate Maltby.
The pornography allegations were first made public last week by the former Met assistant commissioner, Bob Quick.
Green, the first secretary of state, said his accusers had "ulterior motives".
He said: "I reiterate that no allegations about the existence of the parliamentary computers has ever been put to me or to the parliamentary authorities by the police.
"I can only assume that they are made, nine years later, for ulterior motives."
Maltby - touching her knee in a pub and sending her untrue (and) deeply hurtful ".
Quick, who led the investigation into Home Office leaks in which Green's House of Commons office was searched, said pornography was found on a computer there.
Both Stephenson and Quick gave evidence to a Cabinet Office inquiry into Green's conduct last week, led by Cabinet Office senior official Sue Gray.
The inquiry, which is being privately, is also looking at a separate claim that Tory activist in 2015. He also denies that allegation.
Speaking to the BBC, Stephenson said he thought the claim about Green "was not relevant to the criminal inquiry" into Home Office leaks, which began in October 2008.
Green's home and office were searched as part of that investigation and he was briefly arrested in November that year, but the then shadow immigration minister faced no further action.
A review of the police inquiry found that "less intrusive methods" could have been used.
Referring to the pornography allegations, Stephenson said: "I regret it's in the public domain. There was no criminality involved, there was no vulnerability and it was not a matter of extraordinary public interest. "
Stephenson added that it was not Scotland Yard's role to "police the workplace".
The Met declined to say whether it was helping the Cabinet Office investigate the claims, but said in a statement: "
