Oren Dorell

USA TODAY

Pope Francis said he would like to have a historic meeting with the patriarch of the Russian Orthodox Church, but that is unlikely to happen.

Political differences between the churches in Rome and Moscow create "very serious obstacles" to a meeting between the Catholic leader and the leader of the largest Orthodox community, papal historian George Weigel said.

Russian Orthodox politics are so close to the Russian government and its policies that it behaves like "a wholly owned subsidiary of the Russian state," Weigel said. "How can you have a serious theological dialogue with people functioning as (Russian President Vladimir) Putin's agents in Ukraine?"

Francis on Sunday admitted that he is skeptical that such a meeting could happen, listing the war in eastern Ukraine and theological differences, though he said both he and Patriarch Kirill, head of the Russian Orthodox Church, would like to meet.

"I said I'll go wherever you want — you call me and I'll go. And he also has the same desire," Francis said in response to a reporter's question while flying from Turkey back to Rome. "But with the problems of the war, the poor guy has so many problems, so a meeting with the pope will have to wait."

Francis also said it would need to wait "until the theologians agree among themselves."

The two sides have theological differences that date to 1054, when the two churches split. Catholics insist on the primacy of the pope of Rome, while the Orthodox church is less centralized.

"We'll never get to that day, I assure you. I am skeptical," Francis said.

Earlier Sunday in Istanbul, Francis and Patriarch Bartholomew I, leader of the world's Orthodox Christians, issued a joint statement saying they pray for peace in Ukraine while calling for parties to the conflict to engage talks, respect international law and end the conflict.

The Russian Orthodox Church has backed pro-Russian separatists in eastern Ukraine Putin's annexation of Ukraine's Crimea region. Kirill has described the growing closeness of the Ukrainian Orthodox and Ukrainian Catholic churches during the conflict as a threat to the Russian Orthodox Church and its believers in Ukraine.

Followers of the Russian Orthodox Church have persecuted followers of other faiths, including Muslim Tatars in the Crimea, and Catholics and Ukrainian Orthodox and Protestants in eastern Ukraine to the point of torture, exile and death, according to Mission Eurasia, which combats religious persecution in the former Soviet Union.

When the pope speaks of resolving theological differences, he is also lending support to Ukrainian Catholics, who follow Byzantine theological, liturgical and spiritual traditions but rejoined the Rome-based church in 1596, said Mark Morozowich, a priest and interim provost of The Catholic University of America, in Washington, D.C.

The Ukrainian Catholic Church is considered a renegade religion by the Russian Orthodox. It was declared not valid by a Russian Orthodox synod in 1946. Its bishops were imprisoned, many were martyred, and thousands of believers were forced underground. And it's still banned in Russia.

"There are thousands of Ukrainian Catholics in Russia and Siberia who are not allowed the freedom of religion in Russia today. That's part of it," Morozowich said. "Why would Russia be blocking the human rights of these people in Russia to witness and to pray according to their conscience?"

Contributing: The Associated Press.

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