Pope Francis and Russian Orthodox Patriarch Kirill called for Christian unity and said the international community should protect people of faith who are under assault from violent Islamic militant groups.
"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 a joint declaration on February 12 following the first-ever meeting between a Roman Catholic pope and a Russian Orthodox patriarch.
"Their churches are being barbarously ravaged and looted, their sacred objects profaned, their monuments destroyed."
The two church leaders noted that extremist groups like Islamic State have persecuted not only Christians but people of other faiths, including fellow Muslims.
"We wish to express our compassion for the suffering experienced by the faithful of other religious traditions who have also become victims of civil war, chaos, and terrorist violence," they said. "The international community must undertake every possible effort to end terrorism through common, joint, and coordinated action."
As leaders of two of the largest branches of Christianity in the world with 1.3 billion combined followers, they pledged to work for unity in the future.
"For nearly 1,000 years, Catholics and Orthodox have been deprived of communion in the Eucharist," they said in the joint declaration. "We are pained by the loss of unity, the outcome of human weakness and of sin."
"Mindful of the permanence of many obstacles, it is our hope that our meeting may contribute to the reestablishment of this unity willed by God," they said.
It was the first meeting between the heads of the Eastern and Western churches since the great schism of 1054 when the churches split apart, with the Eastern church rejecting the authority of Rome.
Upon meeting for the first time at the airport in Havana, Cuba, the pope and Kirill embraced and Francis exclaimed, "Finally!"
"At last we meet. We are brothers," the 79-year-old Francis told the Orthodox leader. "Clearly, this meeting is God's will."
Kirill told Francis through an interpreter: "Now things are easier."
The Orthodox Church's refusal to accept the pope as the head of Christianity is the main reason for the historically poor relations between the two churches.
More recently, there has been rancor between the Catholic Church and the Russian Orthodox Church, which has the biggest flock in Orthodox Christianity, over property in Ukraine and over the Russian church’s accusations that the Catholic Church seeks to poach converts.
Francis, who became pope in 2013, has sought to bridge the divide and said in an interview this week: "I just wanted to embrace my Orthodox brothers."
Since Kirill is a close ally of Russian President Vladimir Putin, Francis also framed the meeting as a chance to engage Russia, which he said could serve as a key partner to promote peace in the world.
Russia recently has faced scathing criticism for thwarting efforts at peace in Syria by stepping up its military campaign with the Syrian government to retake opposition strongholds in Aleppo and elsewhere.
Russia also has been criticized for sabotaging efforts to settle the conflict in Ukraine, which began after Moscow annexed Ukraine’s Crimean Peninsula in March 2014 and threw its backing behind separatists in the East.
Earlier, the two leaders were greeted by Cuban President Raul Castro, 84, upon their arrival in Havana.
After the meeting, Francis left for a tour of Mexico and Kirill continued his 11-day trip to Latin America that will take him next to Brazil and Paraguay.