According to a BBC report, examining Judge Cristina Di Censo said the process would start on 6 April, after prosecutors in Milan asked for an immediate trial.
Mr Berlusconi denies paying for sex with Karima El Mahroug when she was 17.
He also rejects claims that he abused his power by seeking her release when she was detained in another case.
He has called the accusations “groundless” and dismissed the case as a farce.
Mr Berlusconi does, however, acknowledge that he called the police while she was being held on suspicion of theft.
He said he was doing a favour for the then-Egyptian leader, Hosni Mubarak, because Mr Berlusconi was told the girl was Mr Mubarak’s granddaughter.
Ms Mahroug, widely known as Ruby and now aged 18, has denied sleeping with the prime minister but has said she received 7,000 euros (£5,900, $9,400) from him as a gift after one of his parties.
This media house understand that on Sunday 13th February, hundreds of thousands of Italian women held nationwide protests against their embattled prime minister in more than 60 towns and cities across Italy and overseas.