Turkish President Recep Tayyip Erdogan has said his country will seek “other friends and allies” around the world if the United States continues to take measures against Turkish government officials.

Erdogan’s threat, expressed in an opinion piece published in the New York Times on Friday, comes amid rising tensions in US-Turkish relations over the detention in Turkey of American pastor Andrew Brunson on terrorism charges.

Last week the US government announced sanctions against Turkey’s interior and justice ministers, to which Ankara responded by freezing the assets of two American officials in Turkey.

Although Turkey and the United States have been NATO allies for more than 60 years, the US “has repeatedly and consistently failed to understand and respect the Turkish people’s concerns,” Erdogan said in his opinion piece.

“Unless the United States starts respecting Turkey’s sovereignty and proves that it understands the dangers that our nation faces, our partnership could be in jeopardy.”

He also cited the Turkish invasion of Cyprus as an example of his country’s willingness to protect its interests when the United States “refuses to listen.”

“In the 1970s, the Turkish government stepped in to prevent massacres of ethnic Turks by the Greek Cypriots despite Washington’s objections,” he said, warning that unilateral action against Turkey will hurt American interests in the region. “Failure to reverse this trend of unilateralism and disrespect will require us to start looking for new friends and allies.”