The ongoing Whitehall inquiry into First Secretary of State Damian Green has been widened to look at allegations that pornographic material was found on one of his parliamentary computers, Home Secretary Amber Rudd has said.

Mr Green has strongly denied the claims and called them a political smear.

The Sunday Times reported that ex-Metropolitan Police assistant commissioner Bob Quick alleged the material was discovered by officers during an inquiry into government leaks in 2008.

Mr Green is already the subject of a Cabinet Office inquiry after a woman alleged that he made inappropriate advances to her, claims the First Secretary of State denies.

Ms Rudd told BBC One's The Andrew Marr Show: "I know that the Cabinet Office is going to be looking at this tomorrow along with the wider inquiry about Damian, and I do think that we shouldn't rush to allege anything until that inquiry has taken place."

Mr Quick, who headed the leak investigation, told the newspaper that officers reported finding "extreme porn" on a parliamentary computer from Mr Green's office.

The First Secretary of State, who is effectively Prime Minister Theresa May's deputy, said: "This story is completely untrue and comes from a tainted and untrustworthy source.

"I've been aware for some years that the discredited former assistant commissioner Bob Quick has tried to cause me political damage by leaking false information about the raid on my parliamentary office.

"No newspaper has printed this story due to the complete lack of any evidence.

"It is well known that Quick, who was forced to apologise for alleging that the Conservative Party was trying to undermine him, harbours deep resentment about his press treatment during the time of my investigation.

"More importantly, the police have never suggested to me that improper material was found on my parliamentary computer, nor did I have a 'private' computer, as has been claimed.

"The allegations about the material and computer, now nine years old, are false, disreputable political smears from a discredited police officer acting in flagrant breach of his duty to keep the details of police investigations confidential, and amount to little more than an unscrupulous character assassination."

Police controversially searched Mr Green's Commons office following a spate of leaks of Home Office information.

Mr Quick resigned his post with the Metropolitan Police in 2009 after he was photographed entering Downing Street carrying a secret briefing note on which details of the undercover operation could be seen.

The former anti-terror chief is to give evidence to the Whitehall inquiry into allegations against Mr Green.

The Cabinet Office inquiry was triggered after Kate Maltby, who is three decades younger than the First Secretary of State, told The Times that Mr Green "fleetingly" touched her knee during a meeting in a Waterloo pub in 2015, and a year later sent her a "suggestive" text message after she was pictured wearing a corset in the newspaper.

Mr Green said any allegation that he made sexual advances to Ms Maltby was "untrue (and) deeply hurtful".