Ankara deployed on Sunday military reinforcements to the Syrian border in Turkey's southern Hatay province. The news came shortly after the US-led coalition fighting ISIL announced it was working to create a 30,000-strong border security force in northern Syria.
Spokesman Colonel Ryan Dillon said the coalition and its allies in the Syrian Democratic Forces (SDF) want to focus on border security now that the offensive against ISIL is coming to an end.
The SDF, made up mostly of Arab and Kurdish fighters has flushed out ISIL from swathes of northeastern Syria and controls territory bordering Turkey to the north, Iraq to the east and Syrian government forces to the south and west.
Turkey condemned the coalition’s announcement, saying it would "legitimise a terror organisation".
The SDF is dominated by the Kurdish People's Protection Units (YPG), which Turkey considers a "terrorist" organisation.
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"Rather than end its support to the PYD-YPG, these steps taken to legitimise a terror organisation and to make it permanent in the region are worrying," said Ibrahim Kalin, spokesman for Turkish president Recep Tayyip Erdogan. PYD refers to the Kurds' Democratic Union Party, often considered the YPG's political faction.
"Accepting this state of affairs is absolutely not possible.”
Turkey’s state-run Anadolu news agency reported that tanks and supplies were sent to the troops on the border on Sunday.
Earlier on Sunday, the news agency said that Turkish troops targeted a number of PYD targets in five regions of the Kurdish-held area of Afrin in northern Syria, including Bosoufane, Jindires and Rajo.
Mr Erdogan warned that the Turkish army will attack the Kurdish troops in Afrin "in the days ahead".
Turkey "will continue with the Afrin [operation] — that we started first with Euphrates Shield operation — to purge terrorism from our southern borders," he said on Sunday.
Mr Erdogan also said that he was waiting for backing from allies but did not elaborate.
The government of Syrian president Bashar Al Assad did not immediately respond to the announcement of the border force.
Turkey launched its Euphrates Shield offensive in 2016 to push back ISIL from its border and block the convergence of the Kurdish-run regions.
An estimated 40,000 people were killed in the Turkey-PKK conflict since 1984, and the resumption of fighting in July 2015 has killed more than 3,300 people.
