The radical Egyptian cleric who was kidnapped in Milan by the CIA in 2003 has come to the defence of a former CIA officer convicted for her alleged role in his extraordinary rendition.

Hassan Mustafa Osama Nasr, who is known as Abu Omar, told the Guardian in a telephone interview that he believed Sabrina De Sousa, who faces imminent extradition to Italy, was a scapegoat and ought to be pardoned by Italy’s head of state, Sergio Mattarella. De Sousa, a 60-year-old dual American and Portuguese citizen, faces a four-year prison sentence and is due to be extradited from Portugal on 4 May.

“Sabrina and the others who were convicted are scapegoats. The US administration sacrificed them. All of those higher up in the hierarchy are enjoying their immunity,” he said. “These people higher up, without doubt they should be convicted in this case. They should face trial.”

The remarks mark an extraordinary turn of events in a story that has vexed the US and Italian governments since Abu Omar’s case became public in 2005, exposing in great detail the inner workings of a highly classified and controversial Bush-era counter-terrorism programme. The case also exposed US allies’ help in conducting the secret programme. Abu Omar’s views on De Sousa were first reported by ADNKronos, a wire agency.