ROME — A 10-year legal battle over the “extraordinary rendition” of a terrorism suspect by American intelligence agents seemed to draw nearer to resolution on Tuesday, when the president of Italy commuted part of a prison sentence that one former C.I.A. officer had been given in absentia.

The president’s decree opens the way for the former officer, Sabrina de Sousa, 61, to avoid imprisonment, by serving her remaining sentence some other way, such as through monitored release or community service.

Ms. de Sousa was indicted in 2007, along with 25 other Americans, over the kidnapping of a radical Egyptian cleric in Milan in 2003. Several high-ranking Italian intelligence officials also were indicted, but the case against them fell apart when evidence was withheld from the court on national security grounds.

Ms. de Sousa and the other Americans left Italy before the indictment, so they were tried and convicted in absentia. Most have remained beyond the reach of Italian law by not traveling to Europe. But Ms. de Sousa, who has both American and Portuguese citizenship, moved to Portugal in 2015 for family reasons. Since October 2015, she has been fighting in the Portuguese courts to avoid extradition to Italy; most recently, she was detained on Feb. 21 in Lisbon and was scheduled to be sent to Milan by Thursday.