A Milan judge on Friday rejected a defence motion to suspend a trial over the alleged "extraordinary rendition" of a Muslim cleric from Milan four years ago.
Preliminary hearings judge Simone Luerti ruled that an Italian government appeal to the country's Constitutional Court that prosecutors had overstepped their bounds was not a sufficient reason to halt the proceedings.
Luerti said the prosecution case "did not appear" to have used documents or other material covered by state secrecy rules, according to local media.
The trial of 26 CIA agents and the former commander and deputy commander of Italian military intelligence agency SISMI, Niccolo' Pollari and Marco Mancini, will therefore go ahead as scheduled, starting June 8.
Luerti also observed that it was the Italian government itself that had sealed some 80 documents which Pollari wanted to use to prove his innocence.
Also Friday, on the prosecution's recommendation, Luerti acquitted two SISMI agents, Marco Iodice and Lorenzo Pillinini, who were indicted in February along with their former bosses, the reports said.
The CIA agents will be tried in absentia as the government has not forwarded extradition requests, which the U.S. has said it would not consider.
Prosecutors said the abduction of Egypt-born cleric Osama Moustafa Hassan Nasr, also known as Abu Omar, was carried out by the CIA with SISMI's help.
Omar was recently released from an Egyptian jail where he said he was raped and tortured.
The Italian Constitutional Court last month started reviewing the government's argument that the prosecutors broke state secrecy laws, needlessly exposed agents and damaged relations between SISMI and the CIA.