As UNIAN reported, Ecumenical Patriarch Bartholomew I on January 5, 2019, signed the tomos in his residence in Istanbul, which proclaims the autocephaly of the newly formed Orthodox Church of Ukraine.
Analysts said the ceremony was "the first step in a long road", indicating it was not clear which of Ukraine's bishops would choose to join the new church.
However, the decision has led to a rift between Russian Patriarch Kirill and Vartholomaios, prompting Moscow to establish an exarchate for Western Europe based in Paris and a diocese of the Russian Church in Madrid to serve the needs of the Russian flock in areas under the jurisdiction of the Ecumenical Patriarchate.
"The pious Ukrainian people have awaited this blessed day for seven entire centuries", Bartholomew I said in his address at the Patriarchal Church of St. George.
Bartholomew I, considered first among equals in Orthodox patriarchy, announced the Orthodox Church of Ukraine has become the 15th independent Orthodox church.
Known as a Tomos decree, the document grants autonomy to the Ukrainian Orthodox church which until now has been overseen by Moscow for more than 330 years.
The decree was signed at a landmark ceremony on Saturday, putting the formal stamp on a break with the Russian Orthodox church which has infuriated Moscow.
Ukraine's President Petro Poroshenko, who attended Saturday's signing ceremony, was also present for the mass. Poroshenko said as he thanked the Orthodox patriarch.
Ukraine last month chose 39-year-old Epifaniy to head the new church, in a move which Poroshenko compared to Ukraine's referendum for independence from the Soviet Union in 1991. "(It) will make Moscow's hope of some future pull of Ukraine back into its "orbit" nigh on impossible without the use of overwhelming (catastrophic) military force".
It had been "signed in violation of the canons and therefore not possessing any canonical force", Legoida said in a statement.
Ukrainian leaders see an independent church as a crucial bulwark against Russian interference, but Russia strongly opposes the split, comparing it to the Great Schism of 1054 that divided Christianity into the Eastern Orthodox churches, with leadership based in present-day Istanbul, and the Catholic Church, with its seat in Rome.
It came after Bartholomew I revoked a 1686 ruling that placed Ukraine under the patriarchate in Moscow in October.
Kyiv has been pushing for a church free from Moscow's influence, a campaign intensified after Russia's 2014 annexation of Crimea and amid the ongoing conflict in eastern Ukraine.
Russian Federation long opposed such efforts by the Ukrainians for an independent church, which intensified after Russian Federation seized Ukraine's Crimean Peninsula in March 2014 and began supporting separatists shortly thereafter in parts of Ukraine's eastern regions of Donetsk and Luhansk.