Italian Premier Silvio Berlusconi made a rare court appearance Monday, greetings throngs of supporters gathered outside the courthouse following a closed-door hearing in a tax fraud case he has dismissed as groundless.

Berlusconi waved to reporters from inside a black sedan as he arrived at the courthouse tightly guarded by 100 riot police. After the two-hour hearing, the premier emerged briefly from the car on his way out to thank hundreds of supporters waiting outside.

"Thank you, thank you all," Berlusconi told cheering supporters who waved Italian flags and banners bearing his party emblem. "It all went fine."

Across the street, a much smaller group of detractors booed and called for his resignation.

He premier did not address the court during the closed-door hearing dedicated to technical matters, instead reserving his comments on the case for an on-air phone call to one of his television stations.

Prosecutors in the so-called Mediatrade case allege fraud in the sale of film rights by his Mediaset company in a case identical to an ongoing trial, but with allegations relating to a more recent period. The preliminary hearing will decide whether to indict the premier in what would be his fourth active trial. A decision is not expected before the end of May.

He has always denied wrongdoing and denounced what he says are left-leaning magistrates intent on hurting him politically.

The Italian leader has a history of legal woes but has rarely showed up in court — the last time was in 2003 for a bribery trial in which he was eventually acquitted on one count while the statute of limitations expired on another.

His lawyer, Niccolo Ghedini, repeated on Monday that the premier will attend hearings as his schedule allows.

Berlusconi will attend the next hearing in the Mediatrade case, but it wasn't yet decided if he will attend the opening of his underage prostitution trial next week, Ghedini said.

"The premier was absolutely serene," Ghedini said. Berlusconi made no statements inside the courtroom, but Ghedini does not exclude it in future hearings.

Three more dates have been set for the preliminary hearing judge to hear evidence to decide whether to indict the premier.

"The prosecutors have shown that they want to persecute me and they don't stop even in the face of facts and of ridiculousness," Berlusconi said Monday as he called in to a TV show on one of Mediaset's channels.

Berlusconi said that the prosecutors see him as an "ideological and political enemy" and as "the obstacle preventing the left from gaining power."

"Unfortunately communism in Italy never surrendered and never changed," Berlusconi said. "I am the most accused man in the universe and in history."

Berlusconi insisted that ever since he stepped into politics in the 1990s, he had stopped running his companies to devote himself to public office exclusively.

"These accusations are not only groundless but also ridiculous," he maintained.

His supporters outside, who have set up an open-air tent creating a semi-permanent presence opposite the courthouse as the premier's trial schedule picks up, gave a similar defense.

"It's been since 1994 that the magistrates have been acting against the premier with innumerable trials," said Alessandro Vigentini, a 20-year-old law student who is a member of Berlusconi's party's youth wing. "The premier has never been convicted. This needs to be understood."

Berlusconi has either been acquitted or seen the statute of limitation against him expire.

The case is one of four currently involving Berlusconi — three relate to his business dealings. The only trial related to his personal conduct — the underage prostitution case — begins April 6. Earlier this year, Italy's Constitutional Court watered down a law introduced by his government that shielded him from prosecution.

Contrary to the past, Berlusconi's lawyers insist he plans to attend hearings, barring engagements stemming from his official duty.

Separately, Berlusconi, one of Italy's richest men, disclosed income of euro40.9 million last year, a 77 percent increase over 2009 when he reported euro23 million, according to figures presented as part of regular disclosure for members of parliament. There was no explanation for the increase.