"We will move against them," Shanahan told journalists at the Pentagon ahead of a meeting with his Greek counterpart.
The Greek newspaper Cathimerini referred to Acting Defense Secretary Patrick Shanahan's statement on the approaching collision between the US naval cruiser and a Russian destroyer in the East China Sea, likening it to Turkish activities in the east of the Mediterranean and the Aegean Sea.
For his part, Greek Defense Minister Evangelos Apostolakis, according to the Russian Interfax news agency expressed his country's concern about Turkey's purchase of Russian missile defense systems of the "S-400."
In a speech at a foreign policy and security conference organized by the magazine of Foreign Policy in Washington, Apostolakis said, "Ankara's purchase of these systems will force Greece to reconsider its weapons system."
The Greek minister added, "This deal makes the air defense system in the region in accordance with a different doctrine. If this deal is made, we will re-plan and supply our system."
The Greek minister said that if Turkey got US F-35 fighter jets and Russian "S-400" systems at the same time, this would completely change the balance of powers and stability in the region.
"Turkey will be able to shoot fire at everything that flies," he said.