MILAN - Italian Prime Minister Silvio Berlusconi said an investigation for possible abuse of office over a scandal involving the use of state aircraft means nothing and would be shelved.

Late on Wednesday, news agency ANSA had reported judicial sources saying Rome prosecutors were obliged to open the investigation following a complaint from the Codacons consumer association but that the case could be dismissed quickly.

It means nothing. It will be shelved very soon, Berlusconi told a local TV station via phone. There is a rule, passed by the prime minister's office, that allows the prime minister, when he uses state planes for reasons of security, to take with him people he feels he needs at no cost.

The news comes ahead of this weekend's European elections, but Italians have become accustomed Berlusconi's legal problems after years of investigations and court cases against him.

Prosecutors had already opened an investigation into the misuse of state planes after media reports that guests at Berlusconi's villa arrived on military aircraft, but the initial probe was not targeted at any individual.

The 72-year-old conservative leader is already mired in a scandal over his relationship with 18-year-old aspiring model Noemi Letizia, which has prompted his wife to ask for a divorce and stirred an outcry from the opposition.

Berlusconi, whose popularity has weathered Italy's worst post-war economic crisis, denies a sexual relationship with Letizia and says it is a private matter.

A photojournalist who took pictures of guests at Berlusconi's luxurious Sardianian villa, including Letizia when she was only 17, said he had pictured several people arriving aboard airforce planes, including a well-known Italian musician.

A prosecutor on Saturday granted Berlusconi's request to seize hundreds of photographer Antonello Zappadu's images, taken without his permission from outside the villa using a powerful lens, on the grounds that they violated the right to privacy.

Berlusconi said on Wednesday the pictures showed nothing untoward and were absolutely publishable. He said no rules had been broken regarding the use of state planes in what he called a very petty furor stirred up by the left-wing opposition.