Prosecutors investigating an alleged prostitution ring through which escorts and hostesses were paid to meet Silvio Berlusconi have disclosed that a gay drug dealer is crucial to their inquiries.

A man aged 27 from Bari named only as “Nicola D” is wanted for questioning in connection with unspecified allegations involving cocaine.

Italian media said that “Nic” was well known in Porto Rotondo, Sardinia, where Mr Berlusconi has a villa, and in Bari, where a number of women are being questioned about their part in private parties hosted by the Prime Minister.

Mr Berlusconi is not under investigation and there is no suggestion that he is involved in prostitution or drugs.

Manila Gorio, a transgender television presenter who is close to the women at the centre of the scandal, told The Times yesterday: “Nic invites beautiful girls to parties. He organises club nights and has got many contacts in Rome, Milan, everywhere. He knows businessmen, politicians — many people.”

Several women alleged that they were paid to attend private parties at the homes of the billionaire, aged 72, in Rome and Sardinia. Among them is Patrizia D’Addario, who claims to have audio and video footage secretly recorded at his residence in Rome.

Another woman, who has also been questioned, is Barbara Montereale, a 23-year-old hostess who accompanied Ms D’Addario and a third woman, Lucia Rossini, for a dinner at Palazzo Grazioliin Rome on the night that Barack Obama was elected as US President.

Ms Gorio, 27, who says Ms D’Addario “is almost like a sister to me”, said she believes that an organisation has been shuttling girls back and forth from Bari to Rome and Sardinia for some time. “This story is not finished yet. Many things have yet to come out,” she said. She declined to elaborate.

Ms Gorio, who hosts reality television shows on a local channel, is also close to Angela Sozio, another aspiring model from Bari and a former Big Brother contestant, who was photographed hand-in-hand with Mr Berlusconi at his Sardinian villa in 2007.

“Now it is becoming clear. Pieces of the colourful puzzle are coming together. Some of my closest friends, and girls who appeared on my programme, are now appearing in this scandal. The question is: who is it who is taking them to these places?” she said.

Giampaolo Tarantini, a businessman, aged 34, from Bari who is based in Rome, is under investigation for corruption and abetting prostitution.

It was during an investigation into Tecno Hospital, the medical supplies company he runs with his brother, that he was allegedly heard during recorded telephone conversations discussing the payment of girls to attend parties hosted by Mr Berlusconi. It is understood that “Nicola D” was mentioned regularly during Mr Tarantini’s calls.

Mr Tarantini’s lawyer, Nicola Quaranta, told The Times: “We don’t know who he is. We have no comment. This is gossip. If there is ever a formal prosecution and there are charges of some offence, then we will try to verify the sources and defend ourselves.”

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