A landmark rendition case in Italy involving 26 U.S. officials and a Muslim cleric is expected to reach a verdict shortly, court observers in Milan say.

Italian prosecutors charged the Americans with kidnapping Imam Osama Moustafa Hassan Nasr in Milan more than six years ago and flying him to Egypt where he says he was tortured, The New York Times reports.

All but one of the defendants were believed to be working for the Central Intelligence Agency, and included the CIA's station chief in Milan.

The case is the first of its kind to contest the practice of "extraordinary rendition" in which terror suspects are captured in one country and taken to another for questioning.

At the time of his abduction, Nasr was under surveillance by Italian authorities who suspected him of preaching violence from his mosque and recruiting militants to send to Iraq.

All of the Americans were tried in absentia.