Berlusconi taped a video message the second time in a few days -- to defend himself from the probe by Milan prosecutors into his encounters with the teenager, nicknamed Ruby Rubacuori (Ruby the Heart-Stealer).
The 74-year-old leader charged that the prosecutors used methods worthy of a Mafia criminal and said he would not respond to a summons by the prosecutors this weekend because he does not want to give credence to an investigation he called illegitimate and politically driven.
"There's nothing I should be ashamed of," Berlusconi said. "I would like to go on trial immediately but with impartial judges, not with prosecutors who want to use this case as a means of political fight."
Prosecutors allege Berlusconi paid for sex with the girl, then a minor, and used his office to cover it up. They have forwarded 389 pages of material, including wiretaps, to parliament to get special permission to search some of Berlusconi's properties. Examining the documents will take at least a week, news reports said.
Hours before Berlusconi's video statement, the teenager appeared on a talk show aired on the Mediaset network that the premier founded.
Appearing composed during most of the two 20-minute segments, Ruby said she never worked as a prostitute and that Berlusconi never "put a finger on me."
Ruby, who asked to be called by her real name during the interview, said she met the premier after winding up at his villa last Valentine's Day upon an invitation to dinner by a friend. At the time she was working as a waitress in a Milan restaurant, she said.
She said she introduced herself by her nickname Ruby, and gave her age as 24. She was 17 at the time. She also said she was Egyptian, a lie she said she could not explain.
"He listened without being paid or obligated to do so. I felt heard," she said. "I told him my whole story in sincerity except for my name, my (real) age and for my country."
At the end of dinner, also attended by other young women, Ruby said Berlusconi invited her into his office and gave her an envelope with euro7,000, which she opened in the car.
"I meet him, he and he doesn't put a finger on me," Ruby said. "I think I can speak well of a person like that."
The scandal broke last year when it emerged that Berlusconi had intervened on Ruby's behalf after she was accused of stealing euro3,000 from a friend and detained by Milan police. Reports said at the time that Berlusconi identified her as a relative of Egyptian President Hosni Mubarak's.
Ruby couldn't say how many times she met Berlusconi, but said the visits and contact stopped after the night of May 27-28, when she was released by police into the custody of a Berlusconi aide.
The prosecutors allege several encounters occurred at Berlusconi's villa at Arcore, near Milan, between February and May.
The interview was conducted by Alfonso Signorini, a gossip journalist who is seen as close to Berlusconi. In contrast to photos that show Ruby dressed provocatively some of which she said were taken from her Facebook page she wore jeans, a dark blouse and black boots. Her long hair hung in her face as she spoke.
The girl, now 18, talked about a troubled childhood, at one point with tears in her eyes, and her move to Italy at age 9. While she said she never worked as a prostitute, Ruby said she tried once. But when she undressed and the man put his hands on her, she said she screamed.
"He looked at me, he said, 'Excuse me, isn't this your work?"' she recounted. "I said 'No, this is the first time,"' and explained she needed the money which she said he gave her anyway.
The probe has dominated the political scene since prosecutors confirmed it last week. Critics have called for Berlusconi's resignation, including during two small demonstrations Wednesday in Rome.
In an apparent sign of concern, Berlusconi has appeared in video messages distributed to Italian media twice since Sunday. Still, he has dismissed any suggestion that the scandal might force him to resign.
"What, are you crazy?" he said Tuesday night to a journalist asking is he intended to resign. "I'm having fun."