Pope Francis made a brief stopover in Cuba for a historic encounter Friday with the head of the Russian Orthodox Church, a meeting aimed at bridging a nearly 1,000-year rift in Christianity but whose focus was believed to be the current turmoil in the Middle East.

The two-hour conversation between Francis and Patriarch Kirill I was the first meeting between the religious leaders of the Vatican and Moscow since an 11th-century Christian schism over papal authority and other disputes. The two leaders signed an agreement and praised a new spirit of collaboration but said little about the substance of their talks.

“We spoke as brothers,” Francis said, before leaving Havana for a six-day visit to Mexico. Sitting beside Kirill, with whom he shared an embrace after the signing of the agreement that the pontiff described as “a series of initiatives . . . that are viable and achievable,” Francis said the two men “spoke frankly and without mincing words.”

In brief remarks, Kirill said the two churches would work together “to help Christians all over the world” and to “protect human life.”

The 30-point statement signed by the two leaders pledges new areas of cooperation for the long-estranged churches to protect Christians in conflict zones while affirming a shared opposition to abortion and same-sex marriage.

The declaration praises the demise of “militant atheism” in formerly communist Eastern Europe and urges unity and dialogue as a path to healing the various divisions and schisms among the world’s Christians, including in war-torn Ukraine.

“In many countries of the Middle East and North Africa whole families, villages and cities of our brothers and sisters in Christ are being completely exterminated,” the statement read.

Francis’s Alitalia jet landed just before 2 p.m. at Havana’s José Martí International Airport, and the pope was received by Cuban President Raúl Castro, who walked with him into the meeting.

The small, decrepit airport terminal was an improbable setting for the encounter between Francis and Kirill, two powerful religious leaders in flowing vestments who preside over empires of architectural splendor.

Cuban state television showed images of the men seated beside each other in a room paneled in dark wood, with a large crucifix on the wall behind them.

Cuba as a venue for the meeting fit Francis’s view of the island’s importance. In his statement, the pope thanked Castro for hosting the meeting and said Cuba was becoming “a capital of unity.” The island also is the site of peace negotiations, which Francis has encouraged, between the Colombian government and leftist FARC rebels. And the pope played a key role in the restoration of diplomatic relations between the United States and Cuba.

The meeting Friday has several political dimensions far beyond the Americas.

For the Vatican, the moment culminates decades of overtures to the Russian church. It also could open greater channels with Moscow over the humanitarian fallout from Middle East conflicts, including the flood of refugees into Europe and ravages against ancient Christian communities and their sites by Islamist militants such as the Islamic State.

On Sunday — with an eye toward the upcoming meeting with Kirill — the pope decried the bloodshed in “beloved Syria,” where Russia has carried out airstrikes to aid the government of President Bashar al-Assad.

The United States, Russia and other powers agreed Friday to a “cessation of hostilities” in Syria’s civil war within the next week, as well as humanitarian access to besieged areas. But the pact also leaves room for continued Russian air attacks.

Moscow could view the patriarch’s meeting with Francis as a chance to display Russia’s role in the Middle East and seek stronger bonds with the Vatican at a sensitive time.

Russia faces increasing pressures from the West over flash points such as Ukraine, where Moscow annexed the strategic Crimean Peninsula in 2014 and backs pro-Russian separatists battling the government in Kiev. Meanwhile, Russia has denounced NATO plans to expand forces in Europe.

“To have [the pope], with his internationally recognized authority, not as a critic but as an ally or at least simply as a neutrally silent figure, is highly attractive to Putin and his associates,” wrote Yury Avvakumov , an assistant professor of theology at the University of Notre Dame who specializes in Eastern church affairs.

Vatican contacts with the Orthodox world are not new.

Pope John Paul II — who once praised the East by saying the church must “breathe with two lungs” — made landmark trips to Greece and other mostly Orthodox nations. He also held groundbreaking talks with Ecumenical Patriarch Bartholomew I, who is based in Istanbul and is considered the spiritual head of the patchwork of highly autonomous Orthodox churches and patriarchs.

But the Russian church is by far the most powerful in terms of size, influence and wealth. Its backing for dialogue could begin reshaping the Christian landscape in profound ways.

Chances for a “full and organic reconciliation” between the churches are extremely remote at the moment, said the Rev. Paul McPartlan, a Catholic University professor who has taken part in Catholic-Orthodox dialogue since 2005.

“But this is a step, what I would call a moment of grace,” McPartlan said. “When that happens, other things can flow.”

The fundamental issues of the nearly millennium-old break still loom large: the power of the papacy as well as other theological splits. In recent decades, another point of friction was Orthodox accusations of Roman Catholic reach into traditionally Orthodox regions, such as Ukraine and Belarus, through Vatican-affiliated churches.

Such differences with the Vatican could still block a quest that has eluded the Holy See: an invitation for a papal visit to Russia. Even just arranging the airport encounter took two years of “secret negotiations” by bishops, Francis was quoted as saying in an interview with Italy’s Corriere della Sera newspaper.

The backdrop of Cuba — far from quarrels in Europe — also had resonance.

It gave the Argentine-born Francis an opportunity to showcase his Latin American roots and the reemergence of the Catholic Church on the island, a former Soviet satellite that in recent years also has rekindled relations with Moscow. Francis visited Cuba in September before making his first trip to the United States.

Kirill, who is on a tour of Cuba, Brazil and Paraguay, looks to project Russian influence in the region, including construction of a major Orthodox church in Havana despite relatively few followers. He arrived Thursday in Havana, where he was received by Castro, 84, and the patriarch was also expected to meet separately with 89-year-old former president Fidel Castro, who stepped down in 2006. On Sunday, Kirill will celebrate the Divine Liturgy at Havana’s Russian Orthodox church.

Later Friday, Francis flew into Mexico City’s airport, where he was greeted by mariachi musicians and crowds waving yellow handkerchiefs at the start of a six-day visit to the world’s second-largest Catholic-majority nation after Brazil.

In what is perhaps the most anticipated event of his trip to Mexico, Francis on Wednesday will celebrate a large public Mass in Ciudad Juarez, along the U.S. border, in an appearance expected to highlight the plight of the world’s migrants and refugees. Francis will also visit the southern state of Chiapas, one of Mexico’s poorest, as well as the crime-
ravaged state of Michoacan, a notorious drug cartel battleground.

This story has been updated to correct the name of the Russian Orthodox service to Divine Liturgy.

Murphy reported from Washington.

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