ATHENS – The visit to Greece of Turkey's Foreign Mevlut Cavusoglu is expected to be without much of the usual diplomatic niceties and press releases about progress being made over differences, this time more likely the talk will be tough.

Turkey has been alternating between playing soft and hard over its claims for waters around Greek islands with the European Union backing away from any idea of sanctions under pressure from Turkish President Recep Tayyip Erdogan.

Cavusoglu is due to sit down with Foreign Minister Nikos Dendias and while they are said to be amicable toward each other the stress over Turkey's provocations is fraying relations further.

Their sit-down is also seen as a warm-up act before Prime Minister Kyriakos Mitsotakis and Erdogan are expected to talk on the sidelines of a June 14 NATO meeting in Brussels, said Kathimerini.

Greece is expected to again raise Turkey's maritime deal with Libya dividing the seas between them and claiming waters around Greek islands although no other country in the world nor the United Nations recognizes the agreement.

Another key issue is Erdogan's repeated threats to further violate an essentially-suspended 2016 migrant swap deal with the European Union by flooding the bloc with scores of thousands more, mainly through Greece and its islands.

Two informal sessions of so-called exploratory talks, the 62^nd, which resumed for the first time in four years was limited to the seas dispute but Turkey also wants to put on the agenda its demands for more rights for a Muslim minority in northern Greece which it says should be called Turkish too.

To make his point, Cavusoglu will on May 31 before coming to Athens visit the Muslim communities on May 30 in  Xanthi and Komotini in northeastern Greece after Turkey complained their rights were being denied.

Erdogan fired a warning shot that he'll hang tough when he recited from the Koran inside the ancient Orthodox Aghia Sophia Church in Constantinople that he turned into a mosque, but Greece is expected to tread softly.

Dendias – uncharacteristically – got into it with Cavusoglu in an April news conference in Turkey after they met, surprising his counterpart who later complained that ministers should not talk frankly with journalists.