Turkey accused on Tuesday the United States of stalling in implementing the agreement to create a "safe zone" in northeast Syria.
"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," Foreign Minister Mevlut Cavusoglu told reporters in Ankara.
"We are seeing that the United States is entering a stalling process... and that it is trying get Turkey accustomed to this stalling process."
The NATO allies carried out their first joint military land patrol in the region on Sunday. Turkey wants the operations to expand rapidly and push back Kurdish forces 20 miles (32 km) from the border, creating a zone which Ankara says should be controlled by Turkish troops.
Cavusoglu said Washington's approach so far had served the Syrian Kurdish People’s Protection Units (YPG) more than Turkey.
Turkey wanted to work with the United States, but was prepared to clear the area of the YPG fighters itself if necessary, he added.
The YPG, which has been a main US ally in the fight against ISIS in Syria, is considered a terrorist organization by Ankara, which says it is an extension of Kurdish militants in Turkey.
Cavusoglu’s remarks coincided with the arrival of two top US military officials in Turkey for talks over the safe zone, said the Defense Ministry in a statement.
A delegation headed by Lt. Gen. Stephen Twitty, deputy commander of the US European Command, and Lt. Gen. Thomas Bergeson, deputy commander of the US Central Command, would meet with Turkish military officials.
President Recep Tayyip Erdogan said last week Turkey also aims to send 1 million of the 3.6 million Syrian refugees it hosts to the planned safe zone in northern Syria.