Turkey’s military fired on U.S.-allied Kurdish fighters in northern Syria in a bid to keep them from advancing toward the border, the Turkish prime minister said Tuesday.

The comments by Ahmet Davutoglu were the first time that Turkey has confirmed the use of force against ethnic Kurdish militias in neighboring Syria. The Ankara government — which is facing a Kurdish insurgency at home — fears these militias could carve out a breakaway Kurdish enclave along the Turkish-Syrian border amid Syria’s chaotic civil war.

It also underscored potential friction between the United States and NATO ally Turkey over the Pentagon’s new strategy of providing greater assistance to the Syrian Kurds. […]