The battle over the inheritance of Luciano Pavarotti took a new twist yesterday when it emerged that Nicoletta Mantovani, the widow of the tenor, was suffering from multiple sclerosis.

Ms Mantovani, 38, his second wife, is reported to be in a dispute over his estimated fortune of generous provisions for her. Ms Mantovani is said to be receiving treatment at a clinic in New York, where she has inherited Pavarotti’s apartment.

The news came a day after an Italian prosecutor opened an inquiry into whether Pavarotti “knew what he was doing” when he signed a will at the end of July leaving his American assets to Ms Mantovani. The singer signed the document at his villa in Pesaro, making her the sole administrator and beneficiary of a trust fund controlling all his assets in the United States, including his art collection as well as the New York property.

The tenor died last month from pancreatic cancer at the age of 71. On the day of his funeral Italian media reported that he had fallen out with Ms Mantovani to the point of wanting a separation. This was denied by Terri Robson, Pavarotti’s manager.

There have, however, since been reports of a battle over his will between Ms Mantovani and the three daughters from his first marriage, Giuliana, Lorenza and Cristina. Ms Mantovani has a daughter by Pavarotti, Alice, now 4.

Pavarotti is known to have drawn up three wills: the American one, which is handwritten, last December, and two further documents in Italy in June and July this year.

Chi said that the illness showed the real reason Ms Mantovani had travelled to New York a few days after Pavarotti’s funeral at Modena, his home town. It said that she was being treated at the Multiple Sclerosis Research Centre of New York.

Neither Ms Mantovani nor Ms Robson would comment on the latest report. Franca Corfini Strata, a doctor and wife of Pavarotti’s personal dietitian, said: “We’ve known for eight or nine years about the multiple sclerosis. Luciano and Nicoletta told us themselves.”

The prosecutor in Pesaro, Massimo Di Patria, said this week that he had begun his investigation into the July will after an interview given by Luciano Buonanno, a Pesaro notary, in which he said that he had been “unhappy about some points” relating to the American assets but was prevented by lawyers from raising them with the tenor.

The handwritten will dated December 2006 was less generous to Ms Mantovani, leaving her his properties in Modena and Pesaro and adding: “I make my heirs my daughters Lorenza, Cristina, Giuliana and Alice, to whom I leave all my other goods, shared evenly among them.”

Lawyers for Ms Mantovani argue that it was superseded by the June will, leaving half the estate to his four daughters, 25 per cent to his widow and a further 25 per cent to be divided as the executors decided, and by the July codicil leaving all his American assets to Ms Mantovani.

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