Turkish President Recep Tayyip Erdogan on Tuesday called on NATO to take a stance against the United States, a fellow ally, over its plans to form a 30,000-strong Kurdish-led border security force in Syria.
Turkey has been threatening to launch a new military offensive in Syria against Syrian Kurdish militias, which Turkey considers to be terrorists because of their affiliation with outlawed Kurdish rebels fighting Turkey.
On Monday Erdogan accused the United States of creating an "army of terror" in Syria, along the border with Turkey, and vowed to crush the US-backed border force.
Addressing his ruling party's deputies on Tuesday, Erdogan questioned NATO's stance on the issue, saying: "Hey NATO! You are obliged to make a stance against those who harass and violate the borders of your members."
NATO did not immediately respond to a request for reaction to Erdogan's remarks.