The Metropolitan police’s decision to take no further action over Virginia Giuffre’s allegations of sexual assault against Prince Andrew “comes as no surprise”, a source close to the royal has said.

The force said on Sunday it had dropped the investigation after reviewing several documents, including one relating to an ongoing US civil lawsuit concerning Giuffre, who alleges she was forced to have sex with the prince when she was 17 years old.

The Sunday Times reported that Scotland Yard officers had spoken to Giuffre, although the Met would not confirm or deny doing so.

A source close to Prince Andrew told the PA Media news agency: “It comes as no surprise that the Met police have confirmed that, having reviewed the sex assault claims against the duke for a third time, they are taking no further action.

“Despite pressure from the media and claims of new evidence, the Met have concluded that the claims are not sufficient to warrant any further investigation. The duke has always vigorously maintained his innocence and continues to do so.”

The review was launched after Giuffre filed the lawsuit in August. Insisting that “no one is above the law”, the Met commissioner, Dame Cressida Dick, said that she had “asked my team to have another look at the material”. The Met said while its review was “complete”, it would continue to “liaise with other law enforcement agencies who lead the investigation into matters related to Jeffrey Epstein”.

Giuffre’s lawsuit accuses Andrew of sexually abusing her at the home of the socialite Ghislaine Maxwell in London and at properties owned by Epstein, the disgraced financier who died in prison in 2019 while facing charges of sex trafficking.

A now notorious photo of Andrew with an arm around Giuffre’s waist is said to have been taken by Epstein at Maxwell’s home during a visit to London in 2001, when Giuffre – then Virginia Roberts – was about 17. Sources said to be close to the prince have suggested the photo was faked – a claim vehemently denied by his accuser – while Andrew has said he has “no recollection” of meeting her.

He has “absolutely and categorically” denied having sex with Giuffre and Buckingham Palace has called the claims “false and without foundation”.

Maxwell, who is facing trial in New York next month, has pleaded not guilty to sex trafficking charges regarding her alleged involvement with Epstein.

Andrew has until 29 October to formally respond to the lawsuit, which seeks unspecified damages.