The yellow bus, which has two large photos of the Prince Andrew on the side, was seen driving through Mayfair on Friday. US investigators recently accused the Duke of York of “zero cooperation” in their investigation into convicted sex offender 

 and his co-conspirators.

The FBI, who has been unable to contact the Prince, would like to talk with him regarding his friendship with Epstein, who committed suicide and died in his jail cell last year.

Epstein A banner on the side of the bus read: “If you see this man please ask him to call the FBI to answer their questions.” The banner also featured a URL address for the website of , a US attorney who is representing several of Epstein’s accusers.

Ms Allred is known for taking on controversial high-profile cases and has represented accusers of  and  During a press conference in  last year, she said Prince Andrew had an obligation to meet with investigators to disclose what he knew about Epstein’s behaviour.

Prince Andrew has, for months, been steeped in controversy over allegations that he slept with 

 - a woman who claims she was trafficked by Epstein when she was a teenager.

The Duke has repeatedly denied all allegations levelled against him.

In November, following an interview with

 , which was an absolute fiasco, he ‘stepped down’ from public life and gave up his status as a senior Royal.

In the interview he had expressed his willingness to give testimony under oath to investigators “if push came to shove and the legal advice was to do so”.

The prince was ridiculed for his answers to questions about his conduct and accused of lacking empathy towards Epstein’s victims and failing to show sufficient regret for his friendship with the convicted sex offender.

When asked about his relationship with Epstein, the Duke said: “The people I met and the opportunities that I was given to learn either by [Epstein] or because of him were actually very useful.” He added: “Do I regret the fact that he has quite obviously conducted himself in a manner unbecoming? Yes.” Allred, the lawyer representing some of Epstein’s alleged victims, spoke to reporters in New York on Friday.

“If he thinks we’re going away and forgetting that he has not yet spoken to the FBI, he’s wrong,” Allred said.

“His birthday was this week, 60th birthday, and I hope that he had a very happy birthday.

Life is not as happy for the victims of Jeffrey Epstein.

So this morning I sent him a post-birthday message on a yellow school bus that circled Buckingham Palace.” Buckingham Palace declined to comment