The Duke of York’s lawyers have one week to challenge a decision that he can be formally notified by the UK courts of the US civil sex assault case against him, the high court in London has said. The high court on Wednesday accepted a request by lawyers for Virginia Roberts Giuffre to formally contact him if necessary about her legal proceedings launched in New York. It is understood Prince Andrew’s legal team are contesting the high court decision, as the issue of whether the royal has been properly served with notice in the case continues. The high court said on Friday: “Lawyers for Prince Andrew have indicated that they may seek to challenge the decision of the high court to recognise the validity of the Hague convention request for service made by Ms Giuffre’s lawyers. “The high court has directed that any challenge must be made by close of business on September 24.” Giuffre is suing the duke for allegedly sexually assaulting her when she was aged 17 and a minor under US law, and is seeking unspecified damages. She claims she was trafficked by Andrew’s former friend and the convicted sex offender Jeffrey Epstein to have sex with the royal. Andrew has denied all the allegations. The question of whether Andrew has been properly served with notice of the case was contested during the first pre-trial hearing of the civil case on Monday in New York. David Boies, representing Giuffre, said papers had been “delivered to the last known address of the defendant” and documents had also been sent “by Royal Mail”. Andrew B Brettler, the duke’s US lawyer, said the royal’s team contested the validity of service to date, adding he has not been properly served under either UK or international law. Brettler also described the civil action as a “baseless, unviable and potentially unlawful lawsuit”. He argued Giuffre appeared to have signed away her right to sue Andrew in resolving a separate lawsuit in 2009. Under the Hague service convention, a treaty that governs requests between countries for evidence in civil or commercial matters, Giuffre’s legal team can ask the high court in London to formally notify Andrew about her civil action. It has been reported that the judge in the case, the US district judge Lewis Kaplan, has ruled Giuffre’s legal team can try delivering the papers to Andrew’s Los Angeles-based lawyer, regardless of whether the duke authorised him to accept it.