The United States and Turkey have agreed to set up a joint operation center in Turkey to coordinate and manage a planned safe zone in northern Syria.

Senior military officials of both countries reached the agreement on Wednesday in the Turkish capital, Ankara.

They agreed to establish the center as soon as possible and to help Syrian refugees to move to the zone.

The Kurdish militia fought with US support against Islamic State militants in the civil war in Syria. Kurdish fighters effectively control northern Syria.

Turkey regards the Kurdish militia as terrorists who pose a separatist threat. Turkey has warned the US that it will take military action if a safe zone is not set up.

Many refugees are said to be unwilling to return to Syria because they are afraid of President Bashar al-Assad.

Turkish President Recep Tayyip Erdogan hopes to bring refugees to the safe zone.

Relations between the US and Turkey have been strained since Turkey purchased a Russian missile defense system.

NHK