The NATO allies have agreed to establish what Ankara calls a safe zone along Turkey’s southern border and clear the region of Syrian Kurdish YPG fighters. On Sunday, Turkish and U.S. troops carried out their first joint military land patrol there.

Turkey, which labels the YPG a terrorist organization, wants the operations to expand rapidly as far as 32 km from its border to create a zone controlled by Turkish troops.

Cavusoglu said Turkey wanted to work with the United States but was growing impatient. “Yes, there are some joint patrols but other than that, the steps that have been taken or the steps that are said to be taken are cosmetic steps,” he told reporters.

“We are seeing that the United States is entering a stalling process...and that it is trying get Turkey accustomed to this stalling process,” he said in Ankara, adding Washington’s approach has so far served the YPG more than Turkey, Reuters reported.

The YPG has been a main U.S. ally in the fight against Islamic State in Syria. U.S. support for the fighters has infuriated Turkey and strained ties with Washington.

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