FORMER Italian Prime Minister Silvio Berlusconi was the ringmaster of "bunga bunga" sex parties at his luxurious villa near Milan, giving the go-ahead for young women to perform pole dances and stripteases, according to a court document.

Berlusconi also faces potential expulsion from his Senate seat next week after receiving a final conviction for tax fraud in a separate case.

He was handed a seven-year jail sentence in June for abuse of office and paying for sex with a minor during the parties.

In a document released yesterday explaining the reasons behind the conviction, the court said there was sufficient proof the 77-year-old had sexual relations with former nightclub dancer Karima El Mahroug, who was 17 at the time, in exchange for money and jewellery.

It claimed that he directed women to perform and dance erotically during the parties.

"It is proven the director of the young women's sexual performances was Berlusconi himself," it said.

Berlusconi has described the evenings as "elegant dinners" and is appealing the verdict. He will not have to serve any jail time for the conviction unless it is upheld after two appeals.

The court said it was Berlusconi who decided when to begin "the so-called 'bunga bunga' in which female guests worked to satisfy the desires of the defendant, that is to 'make him feel bodily pleasures', performing pole dances, stripteases, dressing in disguises and fondling each other".

Evidence also shows Berlusconi was aware El Mahroug, also known by her stage name Ruby the Heartstealer, was under 18 at the time, below the legal age limit for prostitution in Italy, the court found.

The prostitution case forms only one part of Berlusconi's legal problems. In August Italy's top appeals court confirmed his conviction for massive tax fraud at his Mediaset TV empire, a decision he says was politically motivated.