YEREVAN, Armenia — Pope Francis denounced what he called the ideologically twisted and planned “genocide” of Armenians by Ottoman-era Turks a century ago as he arrived in Armenia on Friday for a deeply symbolic visit to mark the centenary of the massacre and pay homage to the country’s steadfast Christian faith.

In the most carefully watched speech of his three-day trip, Francis ad-libbed the politically charged word “genocide” to his prepared text that had conspicuously left it out, listing the Armenian genocide alongside the Holocaust and Stalinism.

And rather than merely repeat what had said last year – that the slaughter was “considered the first genocide of the 20th century” – Francis declared it a genocide flat out, setting the stage for another Turkish protest after it withdrew its ambassador last year and accused Francis of spreading lies.

“Sadly that tragedy, that genocide, was the first of the deplorable series of catastrophes of the past century, made possible by twisted racial, ideological or religious aims that darkened the minds of the tormentors even to the point of planning the annihilation of entire peoples,” he said.

“It’s so sad how, in this case and in the other two, the great international powers looked the other way,” he added, referring to the subsequent horrors of Nazism and Stalinism.

In the run-up to the visit, the Vatican had refrained from using the term “genocide,” mindful of Turkish opposition to the political and financial implications of the word given Armenian claims for reparations.

But Francis, never one to shy from speaking his mind, added the word at the last minute in a speech at the presidential palace to President Serzh Sargsyan, Armenian political and religious leaders and the diplomatic corps.

They gave him a standing ovation.

“One cannot but believe in the triumph of justice when in 100 years … the message of justice is being conveyed to mankind from the heart of the Catholic world,” marveled President Sargsyn in his speech to the pope.

Many historians consider the massacres of an estimated 1.5 million Armenians genocide. Turkey rejects the term, says the death figure is inflated and that people died on both sides as the Ottoman Empire collapsed amid World War I.

The Vatican spokesman, the Rev. Federico Lombardi, said Francis always speaks of the need for reconciliation and that his declaration of a genocide must be taken in the context of recognizing a past horror to then move on in friendship and reconciliation. Lombardi denied that the Vatican’s diplomatic speechwriters had intentionally left the word out, saying they had intentionally left it up to the pope to decide what to say.

In a largely Orthodox land where Catholics are a minority, Armenians have been genuinely honored to welcome a pope who has long championed the Armenian cause from his time as an archbishop in Argentina and now as leader of the 1.2-billion strong Catholic Church. His 2015 declaration that the massacres were considered a “genocide” sealed their affection for him.