The UK's top police force says it has "liaised" with the FBI over allegations against billionaire Jeffrey Epstein.
It comes as Prince Andrew faces mounting pressure to speak to the FBI over allegations he slept with an underage girl.
US officials are investigating claims Epstein trafficked women and young girls around the world to be abused.
Scotland Yard has confirmed it was contacted by Prince Andrew's accuser Virginia Giuffre, formerly called Virginia Roberts, but declined to investigate further on the grounds it was a US investigation.
In a statement the Metropolitan Police Service (MPS) revealed it had interviewed her in 2015 but did not launch a full investigation following advice from the Crown Prosecution Service.
Commander Alex Murray said: "In July 2015 the Metropolitan Police Service (MPS) confirmed it had received an allegation of non-recent trafficking for sexual exploitation.
"The allegation was made against a US national, Jeffrey Epstein, and a British woman.
"It related to events outside of the UK and an allegation of trafficking to central London in March 2001."
He said the force takes allegations "seriously" and officers assessed the evidence.
"Officers interviewed the complainant and obtained early investigative advice from the Crown Prosecution Service," he said.
"Following the legal advice, it was clear that any investigation into human trafficking would be largely focused on activities and relationships outside the UK.
"We therefore concluded that the MPS was not the appropriate authority to conduct enquiries in these circumstances and, in November 2016, a decision was made that this matter would not proceed to a full criminal investigation.
"In August 2019, following the death of Jeffrey Epstein the MPS reviewed the decision making and our position remains unchanged.
"The MPS has liaised with other law enforcement organisations but has not received a formal request asking for assistance in connection with this allegation."
Prince Andrew has strenuously denied the allegations he slept with Ms Giuffre and in a recent television interview he claimed he was at a Pizza Express on the day he is alleged to have met her in London.
Ms Giuffre alleges she was forced to have sex with him three times between 2001 - when she was 17 - and 2002.
She is due to address the alleged incidents in an hour-long documentary due to be aired on Monday.
In it she says: "It was a really scary time in my life.
"He knows what happened, I know what happened. And there's only one of us telling the truth."
The prince has faced a growing backlash following his interview over his friendship with convicted sex offender Epstein.
A number of businesses and institutions have since distanced themselves from him and as a result he has stepped back from royal duties.
The prince has said he is "willing to help any appropriate law enforcement agency with their investigations, if required".
