Turkey will start an operation east of the Euphrates river in northern Syria in a "few days", President Tayyip Erdogan said on Wednesday, a move that could further complicate relations with the United States.
Ankara and Washington have long been at odds over Syria policy, where the United States has backed the YPG Kurdish militia in the fight against Islamic State. Turkey says the YPG is a terrorist organization.
"We will start the operation to clear the east of the Euphrates from separatist terrorists in a few days. Our target is never US soldiers," Erdogan said in a speech televised live.
"This step will allow for the path to a political solution to be opened and for healthier cooperation."
Ankara has recently repeatedly voiced frustration about what it says are delays in the implementation of a deal with the United States to clear the YPG from the town of Manbij, just west of the Euphrates.
Turkey said last month that it wanted the agreement on Manbij to be fully carried out by the end of the year. In November, Turkish and US troops began joint patrols in northern Syria.
That cooperation has been complicated as Turkey has shelled Kurdish fighters to the east of the Euphrates.
The YPG still controls a large swathe of northeast Syria, on Turkey's southern border. Turkey regards the YPG as an extension of the PKK militant group, which launched an insurgency against the state in southeast Turkey in 1984.
More than 40,000 people, most of them Kurds, have died in the PKK's conflict with the Turkish state and Ankara fears the fighting could be fueled by the YPG's presence across the border.