NEW YORK (NYTIMES) - The top federal prosecutor in Manhattan said on Monday (March 9) that Britain's Prince Andrew has "shut the door" on helping an investigation into allegations of sex trafficking by financier Jeffrey Epstein and his associates.

It was the second time in less than two months that the prosecutor, Mr Geoffrey S. Berman, has taken the unusual step of publicly pointing out that Prince Andrew has refused to cooperate with the inquiry despite saying he was willing to.

"Prince Andrew has now completely shut the door on voluntary cooperation," Mr Berman, the US attorney in Manhattan, said in response to a question at a news conference on an unrelated matter on Monday. Mr Berman added that his office was "considering its options," without elaborating.

In January, responding to a similar question, Mr Berman had said that Prince Andrew had provided "zero cooperation" in the investigation.

Late last year, Prince Andrew gave a disastrous television interview to the British Broadcasting Corporation about his long relationship with Epstein. The interview shocked many viewers, who said that Prince Andrew's denials of sexual misconduct were unpersuasive and that he seemed to have little sympathy for Epstein's victims.

After the interview, Prince Andrew abruptly announced that he was stepping back from public life, apparently concerned that his televised appearance could threaten the reputation and charitable work of the entire British royal family.

In a public statement at the time, the prince also said: "Of course, I am willing to help any appropriate law enforcement agency with their investigations, if required."

But that help, Mr Berman has now said twice, has not yet been forthcoming.

It remained unclear on Monday exactly what "options" Mr Berman might exercise in further pursuit of the royal. Prosecutors from his office have already reached out to the prince as their inquiry into Epstein's former employees, girlfriends and associates has continued.

As a practical matter, there may be little Mr Berman can do beyond exerting public pressure on the prince.

When someone is reluctant to help with an investigation, prosecutors have the ability to issue a material witness subpoena for their testimony. If the subpoena is ignored, they can then ask a judge to issue a warrant to compel the person to testify.

But such tactics are much more difficult if the person is question is a foreign citizen living abroad - not to mention a member of the British royal family. The US government would have to ask the United Kingdom to extradite the Duke of York as a material witness, a highly unusual proceeding.

Buckingham Palace did not immediately respond to requests for comment. The British Embassy in Washington also declined to comment on what a spokesman said was an continuing legal process.

Epstein hanged himself last summer at the federal jail in Manhattan, where he was awaiting trial on sex trafficking and conspiracy charges. Prosecutors had accused him of sexually exploiting dozens of women and girls in New York and Florida.

Shortly after Epstein's death, Mr Berman said in a statement that the inquiry into the sex-trafficking conspiracy had not yet finished and that prosecutors were committed to standing up for the "brave young women" Epstein had abused. Attorney General William P. Barr has also vowed to bring criminal charges against anyone who helped Epstein.

Mr Berman's statement on Monday suggested that he remains committed to bringing charges in the case without regard to political consequences.

"The Southern District of New York has a long history of integrity and pursuing cases and declining to pursue cases based on only on the facts and the law and the equities without regard to partisan political concerns," he said.

Prince Andrew, 59, said in his television interview that he cannot "shed light" on Epstein's activities for US law enforcement officers because the two had spent only a few days at a time together. He also said that he would have to consult with his lawyers in advance of testifying under oath about his relationship with Epstein.

American prosecutors may be interested in speaking with the prince because of his friendship with Ghislaine Maxwell, a British socialite who was Epstein's former girlfriend. She has been accused in lawsuits of acting as a top recruiter for Epstein, procuring girls and young women for him to sexually abuse.

Ms Maxwell, who has previously denied any wrongdoing, was one of four women named as possible co-conspirators and granted immunity from prosecution in a widely criticised plea bargain that Epstein struck with federal prosecutors in Florida more than a decade ago.

Epstein's death brought renewed attention to his relationships with prominent figures in politics, academia and business. His social orbit included two US presidents - Mr Bill Clinton and Mr Donald Trump - and he cultivated relationships with billionaires like Mr Bill Gates and Mr Leslie Wexner. His friend and former lawyer, Mr Alan Dershowitz, was part of Mr Trump's defence team in the recent impeachment proceedings.