The Kremlin has issued a fresh warning following a key step in Kyiv's quest for an independent church that is recognized by the Orthodox Christian leadership, saying Russia will protect the interests of the faithful in Ukraine if the historic split leads to illegal action or violence.

The October 12 comments from Russian President Vladimir Putin's spokesman, Dmitry Peskov, came a day after Ukraine won approval from a synod led by Ecumenical Patriarch Bartholomew, the Istanbul-based global spiritual leader of Orthodox Christians, to establish an autocephalous -- or independent -- church.

The decision is a blow to Moscow and the Russian Orthodox Church, whose branch in Ukraine had long been accepted by Bartholomew as the legitimate church there. Russian politicians and church officials have repeatedly said they fear a Ukrainian church would seek to take over property controlled by the Moscow-affiliated Orthodox Christian Church in Ukraine.

"Russia's secular authorities surely cannot interfere" in church matters, but Putin's government is paying close attention to the situation and will take "exclusively political and diplomatic" measures to protect people against violence or illegal actions, Peskov said. "Russia, of course, as it defends the interests of Russians and Russian-speakers, as Putin has always said, in the same way...defends the interests of the Orthodox Christians," he said.

"This is if the Ukrainian authorities are unable to keep the situation within legal bounds, if it takes some ugly, violent turn," Peskov said.

Later on October 12, Russian Foreign Minister Sergei described the move as "provocations by Patriarch Bartholomew of Constantinople, undertaken with direct public support from Washington" during a media interview.

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The historic move toward an independent Ukrainian Orthodox Church that is backed by Batholomew's Ecumenical Patriarchate is adding to tension between Moscow and Kyiv, already extremely high following Russia's 2014 takeover of Crimea and as a war between government forces and Russia-backed separatists continues in eastern Ukraine.

Russian officials have sought to justify Moscow's interference in Ukraine by citing what they said was the need to protect ethnic Russians and Russian-speakers.

In the October 11 announcement that it would "proceed to the granting of autocephaly to the Church of Ukraine," the Ecumenical Patriarchate appealed to the rival churches in Ukraine to "avoid appropriation" of monasteries, houses of worship, and other property "as well as every other act of violence and retaliation so that the peace and love of Christ may prevail."

Patriarch Filaret, head of the Ukrainian Orthodox Church of the Kyiv Patriarchate, which is leading the independence drive, said in June that two major monasteries belonging to the Moscow-controlled church should change hands after autocephaly is secured. But at an October 11 news conference, he said, "Moscow wants a conflict but we, Ukrainians, do not."

Bartholomew is considered the leader of the 300 million-strong worldwide Orthodox community, or "first among equals" of Eastern Orthodox clerics.

In a statement on October 12, Metropolitan Antony, the administrator of the Moscow-affiliated church in Ukraine, accused Bartholomew of "choosing the path of schism" and rejected the synod's decision.

Antony also told clergy and believers that it "is prohibited to co-serve or pray" with the two rival churches seeking independence, the Ukrainian Orthodox Church of the Kyiv Patriarchate and the Ukrainian Autocephalous Orthodox Church.

"What happened at the synod in Istanbul yesterday shocked the entire Orthodox world," Antony said in the statement, adding: "In reality, for our church, nothing has changed. We were, are, and will remain the only canonical church in Ukraine."

Ukrainian President Petro Poroshenko, speaking on October 11, described the synod's decision as "something that we have dreamed of, waited for a long time, and fought for all the time."

The Moscow-based Russian Orthodox Church condemned it as "catastrophic." Aleksandr Volkov, a spokesman for Russian Orthodox Patriarch Kirill, said in televised remarks that the Ecumenical Patriarchate "has crossed a red line."

With reporting by AFP, AP, Reuters, Interfax, and TASS