Pope Francis and Russian Orthodox Patriarch Kirill called for restored unity in a historic meeting in Cuba, nearly 1,000 years after the Eastern and Western churches split.
The two men embraced and kissed in the first meeting between a Pope and a Russian church head since the 11th century. The talks, in an airport terminal in Cuba on Friday, resulted in a joint statement calling the protection of Christians in the Middle East.
"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," they said in apparent reference to violence by militant groups such as Islamic State.
"Their churches are being barbarously ravaged and looted, their sacred objects profaned, their monuments destroyed."
They also said large-scale humanitarian aid was required to tend to refugees fleeing Syria and Iraq, lamenting the "massive exodus of Christians."
Cuban President Raul Castro stood to the side during the ceremony, enjoying another moment in the international limelight after receiving Francis last year and restoring diplomatic relations with the United States recently, meeting President Barack Obama in Panama in April.
The two religious leaders came together only a week after the encounter was announced. Such a meeting had eluded their predecessor, but Francis had issued a standing invitation to meet anytime, anywhere.
The moment came while Kirill was visiting the Caribbean island and Francis added a brief stop on his way from Rome to a long-scheduled visit to Mexico.
The venue was a compromise, according to the BBC's Oleg Boldyrev, who suggested to hold the first meeting in Rome or Moscow would have been impossible.
"Finally," Francis said as he and Kirill entered through doors on opposite sides of a room at Havana airport. "We are brothers."
"I'm happy to greet you, dear brother," said the Russian Church leader, who has had to overcome criticisms from conservatives at home who consider Catholicism a deviation from true Christianity.
Francis, dressed in white with a zucchetto, and Kirill, wearing a tall, domed hat that dangled a white stole over black robes, joined arms and kissed on both cheeks.
"It is very clear that this is the will of God," Francis said after the two men talked for two hours.
Their meeting carried political overtones, coming at a time of Russian disagreements with the West over Syria and Ukraine.
The Russian Orthodox Church is closely aligned with the Kremlin, which is in turn an ally of Cuba.
The Argentine pontiff helped the rapprochement between the United States and Cuba after more than five decades of estrangement.
The pope, leader of the world's 1.2 billion Catholics, is seeking to repair a much longer rupture. Eastern Orthodoxy split with Rome in 1054.
The declaration called for Europe to remain faithful to its Christian roots and restated several traditional Christian teachings such as opposition to abortion and marriage being reserved for a man and a woman.
The Russian Orthodox Church takes a stronger stand on these issues in public than Pope Francis, who supports these teachings but often speaks of other issues such as poverty and protecting the environment, which were also mentioned in the text.
Additional reporting from Reuters.