ATHENS: Cyprus is ready to talk with Turkey to resolve differences in a dispute over Mediterranean drilling rights, but only "without blackmail and threats", its president said on Wednesday.

Meanwhile, European Commission President Ursula von der Leyen said nothing could justify the intimidation of Greece and Cyprus by Turkey, which has extended a drilling vessel's operations in disputed waters until Oct. 12.

"Nicosia has been always ready for a dialogue but for that ... to be effective, it needs to be clearly defined based on international law, without blackmail or threats," Cypriot President Nicos Anastasiades said after talks with European Council President Charles Michel, who chairs EU summits.

Anastasiades said Turkey's move to extend the Yavuz drilling ship's operations came at a time when the European Union, of which Cyprus is a member state, was trying to reduce tensions.

Greek Prime Minister Kyriakos Mitsotakis said he too was concerned by Turkey's move to extend the ship's operation.

"Turkey has a choice - it can engage with Europe constructively ... or it can choose to continue sort of these unilateral actions and face consequences," he said in an interview with the Economist.

"All of us hope that the choice, the path is one of a constructive engagement".

EU leaders will look for ways to defuse tensions at a summit on Sept. 24-25.

"In view of the EU Council meeting next week, we underscored the importance of staying united on the messages (to Turkey) and determined to implement our decisions if the illicit actions continue," Anastasiades said.

Turkish Deputy Foreign Minister Faruk Kaymakci told an online panel on EU-Turkey relations that the operations were in response to "unilateral actions" by Greek Cypriots and Greece.