Italian prime minister Silvio Berlusconi said a prostitution probe by Milan prosecutors is a "mud-slinging" attempt to eliminate him from politics. Berlusconi said prosecutors have only collected "chats and conversation without any kind of penal relevance," in an emailed statement yesterday.

Berlusconi faces an investigation in Milan for engaging in prostitution with a minor and abuse of power, prosecutors said on?Friday. He yesterday slammed what he called a plot against him by the country's judges.

"This new judicial machination which has been blown up by the media will not stop us or distract us from our commitment to change the country," he said in a statement.

The inquiry into the affair dubbed 'Rubygate' by the media was launched by prosecutors as Berlusconi was still reeling from a court ruling partially stripping him of political immunity.

It will consider whether Berlusconi had sexual relations with a girl named Ruby between February and May 2010, when she was still a minor.

Berlusconi maintained at least 14 glamorous young women in apartments in a gated complex outside Milan, leaks from prosecutors revealed yesterday. They lived rent-free and were given large sums of cash by the politician, in return for sex, it is alleged.

The existence of the apartments was revealed by Ruby. It emerged last year that Berlusconi had contrived to have her sprung from police custody after she was suspected of theft. He told police they were holding the grand-daughter of President Mubarak of Egypt. A prosecutor in Milan remarked subsequently, "if she's Mubarak's grand-daughter, I'm Queen Nefertiti."

The 72-year-old media mogul, a notorious womaniser, admits that he is "no saint" but has said he never paid for sex. Both he and Moroccan-born Ruby, a disco dancer, whose real name is Karima El Mahroug, have denied having sexual relations.