Pope Francis marked the 100th anniversary of the mass killing of Armenians, using the word "genocide" during a special ceremony on Sunday. The term is likely to severely strain diplomatic ties with Turkey.
Francis said during a Mass at Saint Peter's Basilica that the killing of around 1.5 million Armenians by Ottoman Turks about the time of World War One was "the first genocide of the 20th century."
He told the congregation that "concealing or denying evil is like allowing a wound to keep bleeding without bandaging it."
Turkey angrily denies that the massacre constituted genocide, saying that the toll has been inflated and that those killed were victims of civil war and unrest.
Pope John Paul the Second and the Armenian patriarch issued a joint statement in 2000 calling the massacre "genocide," but Sunday was the first time the word had been used during a Mass in Saint Peter's Basilica.