Police investigating Andrew Mountbatten-Windsor are to speak to Virginia Giuffre's family, Sky News understands.
The former prince was arrested on suspicion of misconduct in public office earlier this year, and released on bail.
And it emerged in May that detectives investigating Andrew will consider allegations of sexual misconduct in their inquiry into potential offences.
Andrew served as the UK's special representative for international trade and investment from 2001 until 2011, when he stepped down amid controversy over his friendship with sex offender Jeffrey Epstein.
Ms Giuffre accused Andrew of sexual assault - which he has vehemently denied. She took her own life in 2025, aged 41.
A Thames Valley Police spokesperson said: "Our misconduct in public office investigation is ongoing. We cannot go into specifics of the investigation, but we are following all reasonable lines of enquiry."
Andrew was arrested on suspicion of misconduct in public office on February 19, and was interviewed under caution before being released under investigation.
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The legal definition of the offence can include a wide range of conduct, including sharing confidential financial information, financial misconduct, wilful neglect of duty and sexual misconduct.
Andrew has strongly denied any wrongdoing.
Searches were also carried out at his former homes in Windsor and Norfolk. Detectives are understood to be working through evidence recovered during the operation.
The investigation was prompted by the release in the US of the FBI's Epstein files in January.
(c) Sky News 2026: Police investigating Andrew Mountbatten-Windsor to speak to Virginia Giuffre's family
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