(CNN) -- Italian Prime Minister Silvio Berlusconi is to be tried on charges of having sex with an underage prostitute and abuse of power..

A judge in Milan has ruled a fast-tracked trial before three judges should begin in the city on April 6.

The case is the latest in a long-running series of legal wrangles featuring the scandal-plagued politician and billionaire media mogul.

What is Berlusconi accused of?

Prosecutors allege that Berlusconi paid for sex with a 17-year-old nightclub dancer, Karima El Mahrough, nicknamed Ruby.

They also claim he abused his position when he intervened to get her released from the jail where she was being held on charges of theft.

In Italy, the age of consent is 14, and it is not illegal to pay for sex. However, paying for sex with a minor (under 18) is a crime, and can be punished by up to three years in jail. Berlusconi has said the dancer had been introduced as a 24-year-old.

Is this the only legal issue facing Berlusconi?

No. The 74-year-old Italian PM, currently serving his third term in office, also faces charges of bribing British lawyer David Mills to secure favorable testimony in legal cases. His trial, suspended last spring after he was granted temporary immunity, resumes next month. Mills denied receiving bribes and his conviction in the case was overturned last year.

He has survived a series of political, corruption and sex scandals over the years, involving allegations of embezzlement, tax fraud and bribery.

Berlusconi has been tried on at least 17 charges since he was first elected prime minister in 1994, but none of the cases have resulted in lasting convictions; several were overturned on appeal.

He has always denied any wrongdoing, and had previously claimed immunity from prosecution, though a 2008 law granting him this was overturned the following year.

How has he reacted to the claims?

Berlusconi insists he has never paid for sex -- "not even once in my life" -- and says any suggestion he did so is "degrading for my dignity."

Both he and El Mahrough, who is now 18, deny ever having had sex with one another. But the young woman's former roommate told investigators that El Mahrough confided to her that she did have a sexual relationship with the premier.

Berlusconi says he did call the police on El Mahrough's behalf, but denies this was an abuse of power.

The billionaire media magnate and football club owner says the allegations against him are simply political mudslinging.

His lawyers have called the investigation "absurd and groundless" and a "grave interference" in Berlusconi's private life.

So what happens now?

Judge Cristina di Censo has ruled that Berlusconi should face trial on the two charges -- having sex with an underage prostitute, and abuse of power.

The court case, before three judges, is due to begin in Milan on April 6.

Berlusconi's lawyers have previously argued that courts in Milan do not have jurisdiction in the case -- because of where the alleged crimes were committed -- or the authority to try a prime minister.

Has the scandal damaged Berlusconi's reputation?

Yes and no. Long-running scandals, a playboy lifestyle and a series of well-publicized gaffes have opened the Italian PM up to ridicule.

There are signs Italians are tiring of the constant focus on his personal indiscretions, and many doubt the situation will improve.

"Should he resign? They all should resign; we are a joke. It is the country of jokes," Fedrica, a 22-year-old coffee shop assistant in Rome told CNN recently.

Thousands of Italians took to the streets in cities across the country -- and in Tokyo and Geneva -- on February 12 in protest at Berlusconi's alleged behaviour towards women.

A poll in the Italian daily newspaper, Corriere della Sera, found 56 percent of those questioned no longer want Berlusconi as PM. A TV poll found 61 percent felt he should resign, but 59 percent believed the government would continue as it is until its mandate ends in 2013.

Berlusconi has survived two votes of no confidence in recent months, and while his personal approval ratings have been dented, his party, the People of Freedom, still enjoys widespread support in Italy.