Nicolo Pollari's defense also requested outgoing Premier Romano Prodi as a witness, said lawyer Alessia Sorgato, who represents some of the American defendants.
Berlusconi _ who won Italy's national elections Monday _ is considered a key witness because he was premier when an Egyptian cleric, Osama Moustafa Hassan Nasr, also known as Abu Omar, was abducted from a Milan street in February 2003.
The alleged kidnapping was part of the CIA's so-called extraordinary renditions program _ moving terror suspects from country to country without public legal proceedings.
Berlusconi's testimony in the Milan trial is being sought to clarify which evidence might be protected as classified and prove that Pollari was against the rendition, Sorgato said. Also among the requested witnesses are the defense ministers and undersecretaries in both Berlusconi's 2001-06 government and Prodi's 2006-08 government.
Judge Oscar Magi will decide May 14 on whether to allow their testimony. On the same day, Abu Omar's wife, Ghali Nabila, and Milan's lead anti-terrorism investigator, Bruno Megale, will also be heard.
The issue of classified documents has held up the trial, which opened in June, for months as the court awaited a decision by Italy's highest court on whether the indictments improperly relied on state secrets as evidence. It is part of the Italian government's request to throw out the indictments.
The high court still has not ruled, but the judge decided last month to resume the trial anyway. The Constitutional Court is set to hear the case July 8.
Italian prosecutors say the cleric was transferred to U.S. bases in Italy and Germany before being moved to Egypt, where he was imprisoned for four years. Nasr, who was released last year, said he was tortured.
All but one American suspect in the case have been identified by prosecutors as CIA agents. Seven Italians also were indicted in the case, including Pollari.
