Foreign Minister Nikos Dendias is in Istanbul, where he has met the Ecumenical Patriarch Bartholomew.
Earlier on Christmas Day, Mr Dendias attended Mass at the Patriarchate.
On Tuesaday, Dendias and his Turkish counterpart, Mevlut Cavusoglu, had a phone conversation.
Diplomatic sources were unable to provide details regarding the content of the discussion between the pair.
Tensions have escalated between Ankara and Athens following Turkey’s maritime boundaries accord with Libya signed last month that ignores territorial waters of a number of Greek islands, including Crete.