A lawyer for trafficking victims of disgraced American financier Jeffrey Epstein said she has given the FBI information from a woman claiming she saw the Duke of York with alleged victim Virginia Giuffre at a London nightclub.
Prince Andrew has previously denied Ms Giuffre's claim he was at the Mayfair establishment with her on the night in question – March 10 2001 – saying he was at home after visiting a Pizza Express in Woking with his daughter Beatrice.
However, US lawyer Lisa Bloom said another woman has come forward to support Ms Giuffre's version of events.
Ms Bloom said Shukri Walker recalls seeing Andrew at the club with Ms Giuffre – then known as Virginia Roberts – and Epstein's girlfriend Ghislaine Maxwell.
Maxwell is now in jail in the US on charges of trafficking minors for her former partner and the British socialite, who has pleaded not guilty, will go on trial in July 2021.
Ms Bloom said she has forwarded Ms Walker's information to the FBI.
Prosecutors working on the Epstein trafficking case have accused Andrew of refusing to cooperate with requests to interview him about his contacts with Epstein, who killed himself in a New York prison last year while awaiting trial on child sex trafficking charges.
Andrew has said in recent weeks that he is cooperating with the FBI investigation into Epstein.
Ms Bloom told the PA news agency in an email: "I can confirm that I spoke to the FBI and gave them all of the information Shukri provided to me.
"She credibly alleges that she was there at the Tramp nightclub in 2001 and specifically recalls Prince Andrew being there with Virginia Roberts Giuffre and Ghislaine Maxwell.
"She had never been in the presence of a royal before or since and so it was very memorable to her.
"She was disappointed when she saw Prince Andrew's now infamous interview where he denied being there."
Ms Bloom added: "I represent six victims of Jeffrey Epstein. We demand that everyone who helped him abuse girls be brought to justice.
"And we demand that everyone with information about Epstein or Maxwell, including Prince Andrew, assist authorities by providing full information and documentation."
Ms Giuffre claimed she had sex with Andrew on three separate occasions, and was aged 17 on the first occasion.
She has claimed in a now-settled US defamation lawsuit – documents from which were released last week – and in other litigation, that Maxwell recruited her in 2000 to be a sexual servant for Epstein.
The duke categorically denies he had any form of sexual contact or relationship with Ms Giuffre.
Ms Walker told The Sun newspaper she recalls Andrew having been at Tramp because she accidentally stepped on his foot while dancing.
She told the paper she had decided to speak out after watching Andrew's denials in his now infamous BBC Newsnight interview about his friendship with Epstein and Ms Giuffre's allegations.
"When I watched the BBC interview and saw Prince Andrew deny knowing Virginia, saying he has no recollection of that night I had to come forward," Ms Walker was quoted as saying.
"Because I was there and I do have a recollection of it."
The Sun reported the FBI had decided it did not need Ms Walker's testimony despite being given her evidence by Ms Bloom.
An FBI spokeswoman told the PA news agency it would not comment on the developments surrounding Ms Walker.