An Italian judge has ordered 26 Americans and five Italians to stand trial for the kidnapping of a terror suspect in Milan in 2003, in what will be the first criminal court case over the CIA’s extraordinary rendition programme.

The decision, which indicts a number of senior intelligence officials from the US and Italy, concerns the abduction of a radical imam known as Abu Omar, who was flown to Egypt where he claims he was tortured under questioning on February 17 2003. Prosecutors say that five Italian intelligence officials worked with the CIA to abduct the Egyptian cleric.

All but one of the American suspects have been identified as CIA agents. Among them are said to be the former heads of the CIA in Rome and Milan - Jeff Castelli and Robert Lady – as well as the former Italian chief of military intelligence, Nicolo Pollari. The other US citizen is an air force officer stationed at the time at Aviano, where Abu Omar was taken after being seized.

Mr Pollari, the only defendant who appeared during the preliminary hearing, has insisted that Italian intelligence played no role in the alleged abduction, and told the judge he was unable to defend himself properly because documents clarifying his position were not permitted in the proceedings because they contain state secrets. The CIA has refused to comment on the case.

Abu Omar, whose real name is Hassan Mustafa Osama Nasr, was allegedly snatched from Milan, where he was transferred by vehicle to the Aviano Air Force base near Venice. He is said to have then been flown to the Ramstein Air Base in Germany, and then on to Egypt, where he says he was tortured by Egyptian agents with electric shocks and threatened with rape.

As well as straining Italian-US relations, the case has put an uncomfortable spotlight on intelligence operations, as prosecutors press the Italian government to seek the extradition of the US agents. The previous government of Silvio Berlusconi refused, and Romano Prodi’s current centre-left government has yet to make its decision.

Even if a request is made for the Americans’ extradition it is highly unlikely that Washington would turn over the CIA agents for trial abroad. All of the US agents have court-appointed lawyers, who have acknowledged having no contact with their clients.

Richard Owen, Times Correspondent in Rome, said that today’s significant decision was enabled partly by a political climate more critical of Washington than under Mr Berlusconi, whose administration had he said displayed a “firm, almost unquestioning support for the Bush administration and the war on terror.”

“Berlusconi himself has always denied having any knowledge of the kidnapping, as has Pollari,” he said. “But the political environment has changed now – Prodi’s Government, although largely loyal to the Atlantic alliance, does contain some strong anti-US elements from the hard-left. This created a climate in which the prosecution of CIA agents became more likely.”

He added that the unlikelihood of the US responding to possible extradition requests meant that today’s move was “partly symbolic”, adding nonetheless that there would be more tangible consequences.

“The prosecution of the Italians will cause serious embarrassment to the former government of Berlusconi and the Italian intelligence service” he said. “The trial will also put a strain on US-Italian relations, amid the climate of Prodi’s centre-left government and its anti-American elements.”

Italian investigators do not question that Abu Omar was suspected of involvement in terrorism. They say their own surveillance of him - including wiretapped phone calls - led them to believe that he had ties to al-Qaeda and was recruiting insurgents for Iraq. They complain, however, that the alleged CIA abduction compromised Italian anti-terror investigations and was a violation of Italian sovereignty.

The cleric was released earlier this week from an Egyptian jail. His lawyer there said that he wants to return to Italy, where he had been granted the status of political refugee.

Although Italy is now likely to be the scene of the first criminal trial for the extraordinary rendition program, there are moves elsewhere in Europe to prosecute those allegedly involved. This week, the Swiss government approved prosecutors’ plans to investigate the flight that allegedly took Abu Omar over Swiss air space, from Italy to Germany.

A Munich prosecutor recently issued arrest warrants for 13 people in connection with another alleged CIA-orchestrated kidnapping, this time of a German citizen who says he was abducted in December 2003 at the Serbian-Macedonia border and flown to Afghanistan.

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