Italian prosecutors filed a request on Wednesday to bring Prime Minister Silvio Berlusconi to trial immediately over the prostitution scandal that has shaken his struggling centre-right government.

Prosecutors accuse Berlusconi of paying for sex with a nightclub dancer when she was under 18, which is against the law in Italy.

They also accuse him of abusing the powers of his office by pressuring police to have her released from custody over theft allegations.

The 74 year-old premier dismissed the accusations as disgusting and disgraceful and said the Milan prosecutors' office was acting for subversive purposes in targeting him.

The prosecutors' application, which means they believe they have enough evidence to skip a preliminary hearing, adds to the already considerable pressure on Berlusconi, who is clinging to power after a split in the ruling PDL party last year.

The move, announced by prosecutors in a dry statement issued as Berlusconi was in Rome outlining a plan to revive the sluggish economy, is likely to be only one stage in a potentially long legal battle with an uncertain outcome.

The billionaire media tycoon, whose immunity from prosecution was struck down last month by the constitutional court, is already on trial in three tax fraud, embezzlement and corruption cases due to be heard in the coming weeks.

He has rejected calls to resign and denies any wrongdoing, accusing magistrates he calls leftist of mounting a politically motivated campaign to destroy him.

I am a rich man who could be spending his life building hospitals for the children of the world as I have always wanted to, he told reporters. But I am performing a service for the country and making a lot of sacrifices.

EVIDENCE

Milan chief prosecutor Edmondo Bruti Liberati's request for a trial had 782 pages of evidence alleging Berlusconi paid for sex with a significant number of young women, including then-17-year-old Moroccan nightclub dancer Karima El Mahroug.

The deposition also alleges that he later exerted improper pressure on officials to have El Mahroug, known by her stage name Ruby, released from a Milan police station after she was detained on unrelated theft allegations.

A judge now has at least five days to decide and no ruling is expected before the beginning of next week. If the request is accepted, the trial could begin within a couple of months.

The abuse of office charge carries a sentence of up to 12 years in jail while the charge of having sex with an underage prostitute carries a sentence of up to three years.

Berlusconi's grip on power was weakened by a split in his centre-right People of Freedom (PDL) party last year that cost him a secure majority in parliament.

Since then, he has clawed back some lost ground in parliament by attracting support from smaller parties.

Opinion polls show the investigation has damaged him but has not delivered a knock-out blow and with the divided opposition presenting little threat, he could return to power if an early election were held.

However, the investigation has added more acrimony to an already toxic political climate which is likely to make much needed reforms more difficult to achieve and increase the chance of a crisis that could pitch Italy into an early election.

Leaked wiretaps from the investigation have been splashed over media with references to bundles of cash, talk of sex games and gifts that would-be starlets allegedly received after attending parties at Berlusconi's villa.

Berlusconi's defence team has presented evidence from dozens of guests saying the parties at his villa were normal, convivial dinners.

He has acknowledged making a call to police on El Mahroug's behalf, saying he had been told she was Egyptian President Hosni Mubarak's niece. He says he did nothing improper and was only trying to avoid a potential diplomatic embarrassment.

I intervened as head of the government because I was concerned there could be a diplomatic incident and because I am accustomed to helping people in difficulty so the accusation of abuse of office is laughable, he said on Wednesday.

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