The Russian Orthodox Church says a decision about the Ukrainian Orthodox Church made by the synod of the Constantinople Patriarchate has forced the Moscow Patriarchate to end its unity with Ecumenical Patriarch Bartholomew of Constantinople, the Istanbul-based spiritual leader of the world's Orthodox Christians.
Metropolitan Ilarion, the head of the church's external relations, made the remarks in a program aired by the Rossia-24 television channel on October 13.
The broadcast came two days after Ukraine won approval from the synod, led by Bartholomew, to establish an autocephalous -- or independent -- church.
Ilarion said Bartholomew had "recognized the leaders of the schism" within the Ukrainian Orthodox Church, "thus legitimatizing the schism that has existed for more than a quarter of a century."
That, Ilarion said, "has made it impossible for us to stay united with the Constantinople Patriarchate."
Ilarion's statement came just hours after President Vladimir Putin held a late-night October 12 meeting with the Russian Security Council to discuss the situation regarding the Orthodox Church in Ukraine.
The Kremlin on October 12 also issued a fresh warning about Kyiv's quest for an independent church, saying Russia would protect the interests of Orthodox Christians in Ukraine if the historic split led to illegal action or violence.
The Russian Orthodox Church vowed on October 13 to respond firmly to the decision by Bartholomew.
Aleksandr Volkov, a spokesman for Russian Orthodox Patriarch Kirill, said the Holy Synod of the Church would "express its position," without elaborating on what measures it might take.
"The synod, which will convene in Minsk (on Monday), will give its final assessment," Volkov told reporters on October 13.
"At any rate, the response will be in kind and tough," he added.
Arriving in Minsk on October 13, Kirill told reporters, "I hope the Orthodox Church will find the strength to overcome hardships...to stay united."
The synod's October 11 decision is a blow to Moscow and the Russian Orthodox Church, whose branch in Ukraine had long been accepted by Constantinople Patriarchate 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, Putin's spokesman, Dmitry Peskov, said on October 12.
Russian Foreign Minister Sergei Lavrov said on October 12 that the Ecumenical Patriarchate's decision was a "provocation" backed by Washington.
The historic move toward an independent Ukrainian Orthodox Church has added to tensions between Moscow and Kyiv, already high since Russia's 2014 seizure of Crimea and the war in eastern Ukraine between Kyiv's government forces and Russia-backed separatists.
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.
WATCH: In one Ukrainian village, a schism has already been playing out with a fight over the only local church.
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.
On October 11, Patriarch Filaret said that "Moscow wants a conflict but we, Ukrainians, do not."
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.
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."