During the first pre-trial hearing on Monday, Lewis Kaplan, the New York federal judge, gave Mr Boies one week to find an alternative means of service.

But he warned Andrew Brettler, the Duke’s new American lawyer, that he was making the case “more complicated” than it needed to be.

“You have a pretty high degree of certainty that he can be served sooner than later,” he said. “Let’s cut out all the technicalities and get to the substance.”

The Duke will have 21 days to respond to the claim when the judge accepts it has been officially served. The next hearing is scheduled for Oct 13.

Ms Giuffre claims she was forced to have sex with the Duke three times when she was aged 17 in New York, London and the US Virgin islands. She is suing him for undisclosed damages. 

Mr Brettler forcefully rejected her claim against the Duke, describing it as “baseless, non-viable and potentially unlawful”.

He has asked for access to a copy of a “secret settlement agreement” Ms Giuffre made with convicted sex offender Jeffrey Epstein in 2009, in which she allegedly vowed not to take further action against the financier or his associates.

The document remains sealed but is said to have prompted the dismissal, by consent, last month of Ms Giuffre’s high-profile civil claim against Alan Dershowitz, Epstein’s former lawyer.