The spiritual leader of Eastern Orthodox Christians worldwide has recognized the independence of the Orthodox Church of Ukraine in Istanbul, formalizing a break from the Russian Patrichate after four centurieis of unity at a Sunday ceremony.

Ecumenical Patriarch of Constantinople Bartholomew I signed the decree of independence, or tomos, in Istanbul on Dec. 6, formalizing a split the Moscow Patriachate which hasstrongly  ondemned it during an ongoing political conflict between Ukraine and Russia.

A "tomos" is a decree and this one officially recognizes an independent Ukrainian Orthodox Church.

Istanbul remained the center of the Orthodox Church after the Muslim Ottoman Turks occupied the city, then known as Constantinople, in the 15th Century.

"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 in the Turkish capital.

The Russian Orthodox Church has repeatedly denounced the creation of an independent Ukrainian church and has cut ties with the Ecumenical Patriachate, the historical seat of the Orthodox faith since Bartholomew approved the Ukrainian church's request for autocephaly, or independence, in October.

"On December 30, 2018, at its session the Holy Synod of the Russian Orthodox Church discussed the grave consequences of the anti-canonical and criminal invasion of the Patriarchate of Constantinople in the canonical territory of the Ukrainian Orthodox Church," said the Russian Orthodox Church in a statement posted on its website on Dec. 28.

"A special emphasis was given to the uncanonical nature of the 'Uniting Council' which took place in Kiev on December 15 and which was attended by members of the schismatic groups led by the Patriarch of Constantinople's representative, Metropolitan Emmanuel of France, and Ukrainian President P. A. Poroshenko," said the statement.

Petro Poroshenko said, "Tomos for us is actually another act of proclaiming Ukraine's independence.

"For Ukrainians, our own Church is a guarantee of our spiritual freedom. This is the key to social harmony."

The event at St George's cathedral was broadcast live on Ukrainian television.

The event at St George's cathedral was broadcast live on Ukrainian television, the BBC reported.

The Russian Orthodox Church is the biggest Eastern Orthodox church.

It is a member of the Geneva-based World Council of Churches along with the Ecumenical Patriarchate and they have offices next to one another at the WCC headquarters.