The Russian Orthodox Church is suggesting postponing a historic meeting of all of the world's Orthodox churches.

The meeting on the Greek island of Crete due to start on Sunday could be the first in more than a millennium.

Hilarion, a bishop who heads the Moscow Patriarchate's department of external church relations, said in a televised statement on Monday that Russia would not take part in it if others are walking out, and suggested the meeting be postponed.

Istanbul-based Ecumenical Patriarch Bartholomew I, who ranks as "the first among equals", hoped that the gathering of leaders of 14 independent Orthodox churches later this month could promote unity among the world's 300 million Orthodox Christians.

Bulgaria's church said last week it would not attend, putting the plans in jeopardy.