Turkish and U.S. soldiers have started independent patrols in northern Syria along the line separating Turkish-controlled areas from the town of Manbij where Ankara says Kurdish militia fighters are based, Turkey's military said on Monday.
Earlier this month Turkey and the United States endorsed a tentative deal to overcome months of dispute over the town.
Ankara has been infuriated by U.S. support for the Kurdish YPG militia - which it views as a terrorist organisation - and has threatened to target Manbij because of the presence of Kurdish fighters there, alongside U.S. troops.
"As per the Manbij Roadmap and Safety Principles previously agreed upon, independent patrol activities by soldiers of Turkish Armed Forces and U.S. Armed Forces have begun on the line between (the Turkish-controlled) area and Manbij," Turkey's armed forces said on Twitter.
Foreign Minister Mevlut Cavusoglu said Turkish soldiers would enter Manbij step by step, without elaborating.
Turkey has launched two cross-border military campaigns along with Syrian rebels in the past two years. The first, dubbed "Euphrates Shield", was aimed at driving away Islamic State and YPG forces from the border, and the second, called "Olive Branch", aimed to clear the YPG from the town of Afrin.
The head of the militia controlling the town, the Manbij Military Council, confirmed Turkish troops had begun patrols. The Manbij Military Council is affiliated to the U.S.-backed and YPG-dominated Syrian Democratic Forces (SDF) in northern Syria.
"On the Manbij side there are Manbij military council and coalition forces doing patrols," Muhammad Abu Adel told Reuters, adding that Turkish troops and their Syrian rebel allies were patrolling the other side.
Turkey considers the YPG an extension of the Kurdistan Workers Party (PKK), which has waged an insurgency since the 1980s. More than 40,000 have died in clashes.
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