Prince Andrew Photo: VCG

 A US-based lawyer for Britain's Prince Andrew on Monday forcefully rejected claims in a civil lawsuit by a woman who accused the prince of sexually assaulting her when she was 17, and challenged whether the case could even be brought.

At a hearing in the US District Court in Manhattan, the prince's lawyer Andrew Brettler also said the plaintiff Virginia Giuffre appeared to have in 2009 signed away her right to sue Queen Elizabeth's second son in resolving a separate lawsuit.

Giuffre, 38, has said Andrew's abuse occurred about two decades ago, around when the financier Jeffrey Epstein was sexually abusing her. Andrew, the Duke of York, has denied Giuffre's accusations.

"This is a baseless, nonviable, potentially unlawful lawsuit," Brettler, who is based in Los Angeles, said at a court conference conducted by phone.

"There has been a settlement agreement that the plaintiff has entered into in a prior action that releases the Duke and others from any and all potential liability," the prince's lawyer added.

Brettler also said Giuffre had not properly served Andrew under UK law and the Hague Convention, including when a process server left a copy on August 27 with a police officer guarding Royal Lodge, the prince's home in Windsor, England.

Giuffre's lawyer rejected that claim. "We have properly served him," David Boies told US District Judge Lewis Kaplan in Manhattan.

Kaplan directed Boies to propose alternative means to serve Andrew, and rejected Brettler's argument that Hague Convention procedures had to be "exhausted" before applying US procedures.