Prince Andrew is agonising over whether to condemn Ghislaine Maxwell after insiders admitted that "this is not a good time to make enemies".
The Duke of York has declined to comment in the days since Ms Maxwell was arrested and charged with grooming underage girls and sex trafficking them for her former boyfriend Jeffrey Epstein.
The Telegraph understands that the Duke is caught in a dilemma over how to proceed as he tries to save his own reputation while facing the prospect of being questioned by the FBI.
After an infamous Newsnight interview at the end of last year, he was roundly criticised for failing to denounce convicted paedophile Epstein, his friend who had died in a jail in New York while awaiting trial on further charges.
He said he did not regret their friendship because he had met "useful" people through Epstein, but a few days later admitted the association with him was "ill-judged" and apologised for it.
Ms Maxwell has not yet been convicted and could further drag Prince Andrew and others into the ongoing FBI investigation.
A source said: "Volatire on his deathbed, who was asked by the priest to renounce the devil, replied: 'This is no time to be making enemies'.
"The same applies to Prince Andrew. He is damned if he does [condemn Ms Maxwell] and damned if he doesn't. This doesn't seem a good time for him to publicly come out and criticise her. It would seem bad timing to do that now."
Ms Maxwell, 58, has been a close friend of the prince for about 30 years. The Telegraph obtained and published a photograph at the weekend showing her sitting on the Queen's throne at Buckingham Palace in 2002 after being taken on a private tour by the prince.
The Hollywood actor Kevin Spacey sat next to her on the Duke of Edinburgh's chair in the Throne Room on the tour, which was set up to greet Bill Clinton a year after he had stepped down as the US president.
Ms Maxwell will appear remotely by video for a July 14 courthouse arraignment and bail hearing according to a court order issued on Tuesday evening. She is facing four counts of grooming and child sex trafficking and two separate charges of perjury.
US District Judge Alison J. Nathan set the date in an order as she announced special arrangements to allow limited public access to the video feed of Ms Maxwell facing charges for the first time in Manhattan federal court next week.
The FBI currently wants to interview Prince Andrew as a witness in the case and has requested assistance from the Home Office to facilitate his questioning. Prosecutors in the US have accused the Duke of refusing to help them with their inquiries, but his legal team insist they have written five times to authorities offering to co-operate.
His friends fear he is being scapegoated for errors made in the earlier police investigation into Epstein, in which the billionaire financier received a short prison term in return for a plea bargain.
Ms Maxwell, the daughter of the disgraced tycoon Robert Maxwell, is being held in the Metropolitan Detention Center in Brooklyn.
She has hired among her legal team Christian Everdell, a former New York prosecutor who helped to convict Joaquin Guzman, known as El Chapo and at one time believed to be the world's most powerful drug trafficker. Guzman is now serving a life sentence in the US.
Prince Andrew has hired a team of lawyers led by Gary Bloxsome, a partner at Blackfords law firm, working alongside Clare Montgomery QC, who is widely regarded as Britain's leading expert on extradition law.
Her clients have included former Chilean dictator Augusto Pinochet, who successfully resisted extradition to Spain 20 years ago.