Ukrainian Orthodox leaders have been pushing for spiritual independence from the Russian Orthodox Church, prompting fierce opposition among the religious leadership in Moscow.
The Russia Orthodox Church has threatened to "sever relations" with the Patriarch Bartholomew of Constantinople, a leader considering the Ukrainian request for ecclesiastical independence.
Metropolitan Hilarion, head of the Russian Orthodox Church's External Relations Department, was quoted by Russian state broadcaster RT as accusing Bartholomew I of acting in a interfering.
He said: "When one brazenly and cynically interferes in the affairs of a local Orthodox Church, one creates not only a hopeless situation, but threatens the global Orthodox world with a schism."
In the months to come, a ruling by Bartholomew I is expected, concerning the bid by the Orthodox Church in Ukraine to break away from the authority of Russian Orthodox Church.
Currently, the Ukrainian Orthodox Church is among several national Orthodox churches whose head bishop reports to the Russian Orthodox Church but many parishes are said to want independence.
But under the proposals, the Ukrainian Orthodox Church would be granted autocephaly status - meaning its head bishop would no longer be accountable to the leadership in Moscow.
Constantinople is the oldest branch of the Orthodox church and Bartholomew I is often referred to as the "first among equals", concerning his seniority.
Bartholomew I upset Russian Orthodox leaders on Friday when he sent two envoys to Ukraine, a move interpreted as a show of support for the Ukrainian Orthodox Church.
Meanwhile, fighting between Ukrainian forces and Russian-backed rebels has gripped eastern Ukraine for four years.
Top picture: Cathedral of Christ the Savior in Moscow
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