Rome (CNN) -- A lawyer for Italian Prime Minister Silvio Berlusconi has asked Rome prosecutors to investigate an alleged attempt to falsify the birth records of the woman at the center of a sex scandal embroiling the prime minister.
The alleged falsification appears to be an attempt to make her appear not to have been a minor when Berlusconi allegedly paid to have sex with her.
Rome prosecutors did not immediately respond to CNN questions about the case.
Authorities allege that Berlusconi had a liaison with 17-year-old Karima el Mahroug, nicknamed "Ruby the heart-stealer," last spring during parties at his villa -- which both deny.
Berlusconi is scheduled to stand trial in April on charges that he paid the underage girl for sex and abused his position as prime minister by trying to get her out of police custody, which he also denies.
The Italian daily Il Fatto Quotidiano reported last week that someone had tried to falsify the birth records.
Berlusconi's lawyer, Nicolo Ghedini. said in a statement that he asked Rome prosecutors to investigate the allegation that two Italian "emissaries" had visited a birth-registry official in Morocco, where el Mahroug was born, and offered bribes to make the young dancer seem older.
The dancer's age is significant because it is illegal to have sex with a prostitute in Italy only if she is a minor.
Ghedini suggested in the statement that he requested the investigation to establish that Berlusconi had nothing to do with any attempt to change birth records.
"We are dealing with something that tries to surreptitiously damage gravely Prime Minister Berlusconi, who is completely estranged to any eventual illegal action," the prime minister's lawyer said in a statement.
Berlusconi has been tried on at least 17 charges since his first term as prime minister began in 1994, but none of the cases have resulted in lasting convictions. Several were overturned on appeal.
CNN's Hada Messia contributed to this report.