An Australian socialite and her daughter say they are unable to provide any "relevant assistance" to investigators searching for Madeleine McCann.

The luxury yacht owned by Rhonda Wyllie and Melissa Karlson, the widow and daughter of the late Perth property tycoon Bill Wyllie, was linked to the inquiry in reports.

The boat, named WillPower, was moored at a marina in Barcelona, Spain, where a woman with an Australian accent reportedly asked a bystander if he was there to deliver her "new daughter" days after Madeleine disappeared.

Private detectives working for the girl's parents, Kate and Gerry McCann, launched an appeal for information last week about the mysterious woman, described as a Victoria Beckham lookalike.Statement released by the Wyllie family

But Mrs Wyllie and Ms Karlson said they were in Antibes, France, on the night in question.

The pair said they could not help the investigators with the investigation but would co-operate with police to confirm the facts.

A statement released through their company said: "The Wyllie Group today confirmed that the Wyllie family were unable to provide any relevant assistance to authorities investigating the disappearance of Madeleine McCann in Portugal in 2007.

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