Britain’s Prince Andrew hasn’t been helpful to federal prosecutors who want to interview him for their sex trafficking probe into Jeffrey Epstein.

“To date, Prince Andrew has provided zero cooperation,” U.S. Attorney Geoffrey Berman said, per the Associated Press. During a news conference outside Epstein’s New York Mansion, Berman said prosecutors and the FBI had contacted Prince Andrew’s lawyers to interview him.

Last November, Prince Andrew announced that he would “step back from public duties for the foreseeable future” following his explosive interview about his relationship with Epstein. His decision came during revived public attention to a woman’s allegation that she had several sexual encounters with him at Epstein’s bidding, beginning when she was 17.

Virginia Roberts Giuffre said that after meeting Epstein in Florida in 2000, he flew her around the world and compelled her to sleep with several older men, including Prince Andrew, two senior U.S. politicians, a noted academic, wealthy financiers, and the attorney Alan Dershowitz, who is now on Trump’s impeachment defense team. Giuffre said she had sex with Prince Andrew three times, including once in 2001 in London at the home of Epstein’s girlfriend, Ghislaine Maxwell.

Each man has denied the allegations. Epstein allegedly killed himself in his jail cell last summer in Manhattan, where he awaited trial for federal sex trafficking and conspiracy charges. He had been accused of sexually exploiting women and girls in New York and Florida.

In Prince Andrew’s statement from November, he announced his plan to “step back from public duties,” and said he regretted his “ill-judged association with Jeffrey Epstein.” He continued, “Of course, I am willing to help any appropriate law enforcement agency with their investigations, if required.”

Berman has echoed the same sentiment: that the investigation didn’t end with Epstein’s death. “Jeffrey Epstein couldn’t have done what he did without the assistance of others, and I can assure you that the investigation is moving forward,” Berman said, per AP.

Two guards who were supposed to be watching Epstein the night he was found dead have since been charged with altering the jail’s logbooks to prove they were monitoring prisoners when instead, they were sleeping or looking at the internet.