LONDON – Heather Mills McCartney, estranged wife of former Beatle Paul McCartney, is to take legal action over a newspaper article alleging she worked as a prostitute in her twenties, her lawyers said on Tuesday.

“Heather is very distressed by this article,” lawyers for the former model said after the weekend allegations in the News of the World tabloid. She called the article “untrue and highly defamatory.”

{In the story, two women identified as former prostitutes say they shared various alleged assignations with Mills, including a threesome with a Saudi prince who paid Mills $10,000 for one night.]

Mills’ lawyers have fought back. “These are not new stories and were refuted by her lawyers four years ago when first raised,” they said yesterday in a statement. “The sources clearly are a variety of unreliable persons who have been paid.”

The statement said Heather, who separated from her multi-millionaire husband last month, is recovering slowly from revision surgery on her leg which was amputated below the knee after a collision with a police motorcycle in 1993.

“She has suffered weight loss, anxiety and sleeping problems as a result of the stress and anxiety of the break-up of her marriage,” the statement said.

But legal proceedings against the newspaper will be deferred until her divorce settlement is concluded, it added.

McCartney, 63, and Mills, 38, announced their separation last month, blaming media intrusion for the collapse of one of the most high-profile showbusiness marriages.

Legal experts believe that McCartney could lose up to a quarter of his estimated 825-million pound ($1.52 billion) fortune after separating from his second wife.

That would equate to roughly one million pounds for every week of their short-lived four-year marriage.