The Duke of York says he is retiring from royal duties because the Jeffrey Epstein scandal has become a "major disruption" for the royal family.
Prince Andrew, 59, said he had asked the Queen for permission to withdraw for the "foreseeable future".
He said he deeply sympathized with Epstein & # 39; s victims and anyone who "wants some kind of closure."
The Duke has faced a growing relapse following a BBC interview about his friendship with the US financier.
His latest move, which Buckingham Palace described as "a personal decision", was taken after discussions with the Queen and Prince Charles.
For several months, the Duke had faced questions about his ties to Epstein – an American financier who at the age of 66 took his own life awaiting trial on charges of sex trafficking.
Virginia Giuffre, one of Epstein's prosecutors, claimed that she was forced to have sex with the prince three times. The Duke has always denied any form of sexual contact or relationship with her.
In a statement, the Duke said: "I continue to unequivocally regret my ill-judged association with Jeffrey Epstein.
"His suicide has left many unanswered questions, especially for his victims, and I deeply sympathize with everyone who has been affected and wants some kind of closure.
"I can only hope that over time they will be able to rebuild their lives."
He added that he was "willing to assist all appropriate law enforcement agencies with their investigations, if necessary".
The BBC's Royal Correspondent Daniela Relph said his latest statement was "completely different in tone" to his latest TV interview and had "addressed all the issues he had been criticized for", including sympathy for the victims.
She described his decision to go back as a "drastic" move but said that "rumors that had circulated had really been difficult for the royal family to deal with".
"I can't say enough that this statement is unparalleled – for a king to step down, due to a scandal in this way," she added.
In his interview with BBC Newsnight on Saturday, the Duke said that "the opportunities I got to learn" about business meant he did not regret his friendship with Epstein, although he said it was the wrong decision to meet him for a final time in 2010. ".
The Duke said he couldn't remember ever meeting Giuffre and said that in the evening she claims that they first met that he went to Pizza Express in Woking and then returned home.
He tried to cast doubt on her testimony, claiming he was "sweating" in a nightclub, saying that a medical condition at the time meant he couldn't sweat.
He said he had met Epstein "through his girlfriend back in 1999" – a reference to Ghislaine Maxwell, who had been a friend of Prince Andrew since she was at university.
Since the interview, a letter written in 2011 to the Times magazine by Buckingham Palace has emerged that they met in the early 1990s.
The Duke's website says he is performing official duties for the Queen, focusing on promoting economic growth and skilled jobs.
Over the past two months, he has made international engagements in Australia, the United Arab Emirates and Thailand.
BT became the latest in a series of organizations that distanced themselves from Prince Andrew after the interview.
In a statement, the company said it had been working with iDEA – which helps people develop digital, business and employability – since 2017 but "our business has been with its CEOs not its protectors, the Duke of York".
"In light of the latest developments, we are reviewing our relationship with the organization and hope that we may be able to continue working with them in the event of a change in their protection," said a spokeswoman.
Standard Chartered Bank and KPMG also announced that they were withdrawing support for the Duke's Pitch @ Palace initiative. Sources told the BBC that the decisions were made before the interview.
Four Australian universities also said they would not continue their involvement in Pitch @ Palace Australia.
Prince Andrew canceled a planned flooding visit in Yorkshire on Tuesday, the Sun newspaper reported.
The Prince Andrew & Epstein scandal: The Newsnight interview was shown on BBC Two on November 16, 2019 and can be viewed on BBC iPlayer in the UK. The entire interview can also be viewed on Youtube.