Greece's police announced that the state authorities intend to file espionage charges against two citizens working on the southeastern island of Rhodes.
According to Greek media, the two men are believed to be spying for Turkey.
One of the two suspects works on a ferry from Rhodes to an island off the Turkish coast, while the second works at the Turkish consulate in Rhodes.
According to Greek media reports, the suspect on the ferry was providing the second suspect with information about the locations of the Greek navy ships and other matters related to the Greek army on the island.
On Friday, Greece announced that the European Council imposed sanctions on Turkey during a meeting of European Union leaders in Brussels, stressing that these sanctions will be expanded after the French President Emmanuel Macron suggested that the sanctions may affect Turkish officials and sectors.
Athena stressed that the Turkish provocations against the European Union have become clear and absolute, pointing out that the European position is a strong warning to Turkey to change its behavior.
The disputes between Athens and Ankara escalated with Turkey's deployment in August of the ship Oruc Reis to conduct exploration operations in maritime areas disputed with Greece and Cyprus.
France, Greece and Cyprus are seeking action against Turkey, but other countries in the union, including Germany, Italy and Poland, oppose widespread sanctions or an embargo on a member state of NATO.