The Russian Orthodox Church announced Monday it would break ties with the Orthodox Patriarchate of Constantinople over the latter's recognition of a new Ukrainian church, the latest development in a major restructuring of the world's second-largest Christian denomination.
Unlike Catholicism, which has a centralized hierarchy of authority, Orthodox Christianity has several churches spread out across the world, each with their own jurisdiction and leaders. However, the Patriarch of Constantinople is considered a "first among equals" in the Church leadership.
Traditionally, Orthodox churches in Ukraine have fallen under the jurisdiction of the Patriarch of Moscow. But the 2014 annexation of Crimea and Russia's continued support for separatists fighting against Kyiv in the east drove a wedge in relations that led Ukrainian clerics to declare their own autonomous church.
Patriarch Bartholomew of Constantinople officially recognized the new Ukrainian Orthodox Church of Ukraine on Oct. 11, sparking celebration in Kyiv and outrage in Moscow. The Russian Orthodox Church's cutting of ties with Constantinople is a direct result of that decision.
Now priests from the two churches will be barred from serving together, while worshippers of one will not take communion in the other.
The schism is the most significant Orthodox Christianity has experienced since it split from Catholicism almost a thousand years ago. About 100 million of the world's 260 million Orthodox Christians live in Russia, according to the Pew Center.