Ms Giuffre is suing the duke in her home country of the US, claiming she was trafficked by Jeffrey Epstein, Andrew's friend and a convicted sex offender, to have sex with the royal when she was 17 - a minor under US law.

The duke is also alleged to have sexually abused Ms Giuffre during a visit to Epstein's private island, Little St James, and on a separate occasion at Epstein's Manhattan mansion.

The duke has denied all of the allegations.

Earlier in January, it emerged that Ms Giuffre's lawyers requested help to get testimony from two potential witnesses in the UK, including the duke's former assistant Mr Olney.

Court documents revealed Judge Lewis A Kaplan wrote to the Senior Master of the Queen's Bench Division with the aim of having Mr Olney testify about the duke's communications with Epstein, Ghislaine Maxwell and Ms Giuffre, and the duke's travel to Epstein's properties.

In a separate letter to the High Court, the judge also requested testimony from Shukri Walker - the second potential witness in the UK, who claims to have seen Andrew in Tramp nightclub in London.

Ms Walker's testimony should cover questions about the presence of the duke and Ms Giuffre at the nightclub in March 2001, and any interaction between the pair, the judge said.

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Meanwhile, Judge Kaplan has also written to the Australian Attorney General requesting assistance in getting testimony from Ms Giuffre's husband Robert, and her psychologist Dr Judith Lightfoot.

The judge asked for Mr Giuffre's testimony to include how he met his wife, any discussions they had about Andrew, her alleged childhood trauma and abuse, and her relationship with Epstein and Maxwell.

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The letter also requests testimony about the emotional and psychological harm Ms Giuffre says she has suffered, the Giuffre household finances, and her role in trafficking and recruiting young girls for Epstein.

The judge asked Dr Lightfoot to give evidence about Ms Giuffre's medical treatment, her diagnosis, childhood trauma, the theory of false memories, and her claims regarding Andrew.

All four witnesses have been asked to complete their testimony by 29 April.