ISTANBUL (Reuters) – Turkish President Tayyip Erdogan and Greek Prime Minister Kyriakos Mitsotakis agreed in talks on Sunday to improve ties, despite the long-running disagreements between the two NATO members, Ankara said.

Both countries have key roles to play in the changing security situation in Europe after Russia’s invasion of Ukraine, and their increased cooperation would have benefits for the region, the Turkish presidency said in a statement.

Turkey shares a maritime border with both Russia and Ukraine in the Black Sea, has good relations with both countries and has offered to mediate in the conflict.

After a five-year hiatus, Greece and Turkey agreed last year to resume exploratory talks to address their own differences in the Mediterranean, but little progress has been made so far.

“Despite the disagreements between Turkey and Greece, it was agreed at the meeting to keep communication channels open and to improve bilateral relations,” the statement said.

“Pointing out that Turkey and Greece have a special responsibility in the changing European security architecture with Russia’s attack on Ukraine, the meeting focused on the mutual and regional benefits of increasing cooperation between the two countries,” it added. Russia calls its actions in Ukraine a “special operation”.

Ankara and Athens have been at odds for years over issues ranging from conflicting Mediterranean maritime claims to air space and migration.

Greece said that both sides stressed building a positive agenda mainly in the area of the economy, where they hope to make progress in the coming months.

“We have big differences which cannot be overcome just like that,” Mitsotakis told Ecumenical Patriarch Bartholomew after meeting Erdogan.

“I believe we set the foundations to improve our relations,” he said, adding that if there was good progress, Greece might organise in autumn a High-Level Cooperation Council meeting, a mechanism the two countries set up in 2010 for their rapprochement.

The countries came close to confrontation in 2020 when Turkey sent a drilling ship to contested Mediterranean waters. The situation eased after Ankara withdrew the vessel, and the neighbours resumed bilateral talks in January 2021.

They made little progress in 60 rounds of talks from 2002 to 2016.

(Additional reporting by Yesim Dikmen; Writing by Daren Butler; Editing by Hugh Lawson and Andrew Heavens)