Abu Omar was allegedly kidnapped from a Milan street

The suspects are accused of abducting Osama Mustafa Hassan, also known as Abu Omar, without Italian permission, and flying him to Egypt for interrogation.

The new warrants allow for the suspects' detention anywhere in the 25-nation EU, a prosecutor said.

The authorities had already issued arrest orders within Italy.

The BBC's defence correspondent, Rob Watson, describes the case as one of the best documented alleged cases of the CIA's policy of extraordinary rendition.

Extradition unlikely

Italy says the alleged operation hindered Italian terrorism investigations.

No arrests have so far been made.

All 22 suspects are thought to have returned to the US, a formal Italian extradition request seems unlikely, our correspondent adds.

Italian Justice Minister Roberto Castelli has signed the warrants, a move officials described as a formality.

There was no word on whether Mr Castelli would seek extradition, but he has previously accused the judge involved of being a leftist militant and anti-American.

Italy's Prime Minister Silvio Berlusconi is a close US ally and has said he can see no basis for the case.

'No knowledge'

The extraordinary rendition policy involves seizing suspects and taking them to third countries for questioning without court approval.

It has been the subject of controversy recently, with human rights groups alleging that suspects are tortured, and that the CIA has secret prisons where it keeps prisoners without reference to US or international law.

US Secretary of State Condoleezza Rice recently defended the use of rendition, saying it was an established practice and suggesting it was often carried out with the knowledge, or participation, of European governments.

Mr Hassan, 42, is believed to have been abducted on 17 February 2003, and flown out of the country from a US base in Aviano, north of Venice.

He reportedly called his family last year, telling them he had been tortured with electric shocks during his detention.

The CIA has refused to comment on the case and the Italian government has said it had no prior knowledge of any kidnap plot.

Mr Hassan is believed to have arrived in Italy in 1997, where he was granted refugee status.