(Reuters) Fener Greek Patriarch Bartholomeos had invited leaders to come to Istanbul to boost unity among a faith community riven by conflicting loyalties and power struggles.

The emergence of new national Orthodox Churches in former Soviet states as well as tensions among the Orthodox diaspora has exacerbated bitter disputes over theological issues and property ownership.

Russian Patriarch Alexiy II made a rare trip to Turkey to attend the event since the 1900s, and co-celebrated mass with other Orthodox leaders.

Relations between him and Bartholomeos have been strained in the past as some Churches in former Soviet countries such as Estonia have broken away from the Russian Orthodox Church and sought to pledge their allegiance to Bartholomeos instead.

Bartholomeos, an ethnic Greek but a Turkish citizen, presides over a community of only several thousand Greek Orthodox in Turkey, a Muslim country.

In a statement released after their weekend meeting, the Orthodox leaders welcomed Bartholomeos’ proposal for a pan-Orthodox summit in 2009 to resolve internal divisions.

“It really is an urgent matter to call such a pan-Orthodox conference. There are so many problems and theological issues which have not been tackled, and this should have happened long ago,” said Canon Michael Bourdeaux, president of the Keston Institute, which studies religion in former Communist states.