Egyptian cleric Hassan Mustafa Osama Nasr, also known as Abu Omar, speaks to the media at a court house in Alexandria February 22, 2007. REUTERS/Stringer

MILAN (Reuters) - An Italian judge on Wednesday ordered the resumption of a trial against U.S. and Italian spies accused of abducting a terrorism suspect, in a blow to efforts to halt a case that Rome says violates state secrecy rules.

The trial in absentia against 26 Americans -- almost all believed to be CIA agents -- is the first anywhere over the U.S. practice of “extraordinary rendition”, whereby terrorism suspects are secretly transferred to third countries.

Italian spies, including the former head of Italy’s military intelligence agency Nicolo Pollari, are accused of helping the CIA team abduct Muslim cleric Hassan Mustafa Osama Nasr in 2003 and fly him to Egypt. There, Nasr says he was tortured.

Judge Oscar Magi had suspended proceedings shortly after they began in June last year, saying the criminal trial should wait until Italy’s highest court ruled whether prosecutors had broken state secrecy rules when building their case.

But after months of high court delays, Magi decided the trial in Milan could go forward regardless.

“The measure suspending (the trial) can be removed,” Magi told the court. “It will not cause any harm to the defense”.

Prosecutors say a CIA-led team grabbed Nasr, also known as Abu Omar, off a Milan street, bundled him into a van and drove him to a military base in northern Italy.

He was then flown to Egypt, where Nasr says he was tortured under interrogation with electric shocks, beatings, rape threats and genital abuse.

Nasr was freed from prison in February last year and lives in Egypt. He faces an arrest order in Italy on suspicion of terrorist activity.