* Underage prostitution case to open after months of scandal
* Berlusconi denies charges, says targeted by magistrates
* Approval hit but premier resists calls to resign
Milan judges open one of the most sensational trials in recent Italian history on Wednesday when they begin hearings into charges that Prime Minister Silvio Berlusconi paid a teenaged nightclub dancer for sex last year.
The so-called "Rubygate" case has gripped media attention like few others and has completely overshadowed Italian politics for months.
The hearing, set to open at around 0730 GMT, is likely to be a low-key, technical affair. Neither Berlusconi nor his chief lawyers are expected but hundreds of journalists and camera crews are likely to gather outside the court in Milan.
Berlusconi is accused of giving cash and jewels to Moroccan-born Karima El Mahroug in exchange for sex when she was only 17 years old and thus too young under Italian law to be paid as a prostitute.
He is also accused of abusing the powers of his office to have her released from police custody over unrelated theft allegations in an apparent bid to prevent details of their connection emerging in official evidence.
Berlusconi has denied the charges against him and has launched a string of bitter attacks on what he describes as leftist magistrates determined to destroy him politically.
Already hit by a party revolt last year that nearly sank his centre-right government, he has been hurt by the affair, which has drawn condemnation from women's groups, the Catholic Church and even the country's main business lobby.
But public opinion in Italy, traditionally forgiving in questions of private morality, has not been as damning as it would be in many countries and his parliamentary majority has been strong enough to see off opposition calls to resign.
BUNGA BUNGA
No verdict is expected for months and legal manoeuvring may push the case into the kind of judicial limbo that has seen many past cases involving politicians run into the sand.
But even by the turbulent standards of Italian politics, the accusations are extraordinary and would almost certainly have ended the career of any other European leader, especially given the raft of unsolved problems facing the government.
Newspapers have given their readers a lurid picture of life at Berlusconi's palatial private residence outside Milan, describing "bunga bunga" sex parties with dozens of young women who would leave carrying envelopes stuffed with bundles of cash.
Berlusconi, one of Italy's richest businessmen, admits a fondness for young women but has dismissed the scandalous stories, saying the dinners he regularly holds are quiet, convivial occasions where guests eat, tell jokes and sing songs.
He says the presents of cash, jewels, cars and houses investigators say were given to the young women who attended were no more than generous gestures which his vast fortune easily permits.
He has pledged to fight the accusations head on and his supporters believe that the months of scandal mean he has little to fear from new revelations emerging to damage his reputation.
But many in Italy also feel he has been focusing on his legal battles rather than on problems such as a 30 percent youth unemployment rate that makes stories of teenagers taking home cash-stuffed envelopes particularly sensitive.
