Greece made a formal protest to Turkey on Wednesday involving accusations that the fellow-NATO member conducted unauthorized military flights over inhabited Greek islands.
"These actions constitute a violation of Greece’s sovereignty, they are an unacceptable provocation and run contrary to fundamental principles of international law," Greece's Foreign Ministry said in a statement.
Turkey’s ambassador to Athens was summoned to the ministry to receive the complaint in person. Turkey did not immediately respond publicly to Wednesday’s complaint.
Neighbors Greece and Turkey have long-standing sea and air boundary disputes that intensified with moves to explore potential undersea natural gas reserves.
The disagreement has resulted in near-daily air force patrols and interception missions, mostly in disputed airspace around Greek islands that are near Turkey’s coastline.
Greek Prime Minister Kyriakos Mitsotakis met in Istanbul with Turkish President Recep Tayyip Erdogan last month after Russia's invasion of Ukraine became an urgent topic among NATO allies.
But Athens maintains that Turkey has stepped up hostile air force patrols in recent weeks to include overflights of the eastern islands.