Coast guard officers warned off Panos Kammenos, who was heading to the Kardak islets in an assault boat to lay a wreath there.
Following the warning, the Greek boat left Turkey’s territorial waters without further incident, it added.
In a statement, Turkish Interior Minister Suleyman Soylu said the coast guard units “did what was necessary.”
The Turkish General Staff also said in a written statement that the Greek naval vessel Nikiforos and a Greek Coast Guard boat had been moving towards the islets at 11.30 a.m. local time (0830GMT).Their approach was blocked by Turkish Naval Forces and Coast Guard units, said the military.
It added that the Turkish Armed Forces continue to determinedly protect the nation's rights and interests stemming from international law and agreements.
A decades-long dispute between Turkey and Greece over the uninhabited Aegean islets brought the two countries to the brink of armed conflict in 1996 and led to renewed tensions this year.