ANKARA — Turkey on Tuesday called on Greece to withdraw its armed forces from Aegean islands, warning that his country will challenge the status of the islands if it fails to demilitarize them.

Turkish Foreign Minister Mevlut Cavusoglu said during a joint news conference with his North Macedonian counterpart, that Greece has been building a military presence on the Aegean islands in violation of the 1923 Treaty of Lausanne and the 1947 Paris Treaty. He said the islands were ceded to Greece on condition that they be kept demilitarized.

“The agreements are there but Greece is violating them. It’s arming them. If Greece does not stop this violation, the sovereignty of the islands will be brought up for discussion,” he said. “It’s that clear. You will abide by the agreements.”

Read more: Greece Rejects Turkey’s Arguments about Demilitarizing the Islands

Greece argues that Turkey has deliberately misinterpreted the treaties regarding armed forces on its eastern islands and says it has legal grounds to defend itself following hostile actions by Ankara including a long-standing threat of war if it extends its territorial waters.

The Turkish minister’s comments come amid a new escalation in tensions between the NATO allies that have a history of disputes over a range of issues including mineral exploration in the eastern Mediterranean and rival claims in the Aegean Sea.

Last month, Turkish President Recep Tayyip Erdogan said he would stop talking to Greek Prime Minister Kyriakos Mitsotakis, voicing displeasure at comments the Greek leader made during a recent U.S. trip, including suggestions that Congress should block Turkey’s acquisition of F-16 fighter jets.

In Athens, Mitsotakis said restraint was needed on both sides of the Aegean due to the war in Ukraine.

“I think we are still very far from that point, far from the tension we had in the summer of 2020,” Mitsotakis said in reference to a time when tensions flared between Greece and Turkey over gas exploration rights in the eastern Mediterranean.

“Today, everyone needs to show restraint. Especially at a time when we are facing a very big challenge at NATO with the Russian invasion of Ukraine. We must be united,” he said.

Cavusoglu said Ankara had sent two letters to the United Nations on the issue of the militarized islands and he called on Greece to respond to the letters.

“They are getting aggressive because they cannot respond to the letters,” the minister claimed.