The comments, from the spokesman for President Recep Tayyip Erdogan’s government, underscore the growing bilateral tensions, six days after Turkey launched its air and ground operation, “Olive Branch,” in Syria’s northwestern Afrin region.
Turkey’s targeting of the YPG, which it views as a security threat, has opened a new front in Syria’s multi-sided civil war.
Any push by Turkish forces toward Manbij, part of a Kurdish-held territory some 100 km east of Afrin, could threaten US plans to stabilize northeast Syria and bring them into direct confrontation with US troops deployed there.
“Those who support the terrorist organization will become a target in this battle,” Deputy Prime Minister Bekir Bozdag said.
“The US needs to review its solders and elements giving support to terrorists on the ground in such a way as to avoid a confrontation with Turkey,” Bozdag, who also acts as the government’s spokesman, told broadcaster A Haber.
The US has around 2,000 troops in Syria, officially as part of an international, US-led coalition against Daesh. Washington has angered Ankara by providing arms, training and air support to Syrian Kurdish forces that Turkey views as terrorists.
US forces were deployed in and around Manbij last March to deter Turkish and US-backed fighters from attacking each other and have also carried out training missions in the area.
US President Donald Trump urged Erdogan on Wednesday to curtail the military operation in Syria, the White House said.
However Turkey has disputed that characterization of the conversation.
“President Trump did not share any ‘concerns about escalating violence’ with regard to the ongoing military operation in Afrin,” a Turkish official said.
“The two leaders’ discussion of Operation Olive Branch was limited to an exchange of views,” the official said.
Six days into the campaign, Turkish soldiers and their Free Syrian Army (FSA) fighter allies have been battling to gain footholds on the western, northern and eastern flanks of Afrin.
They appear to have made only limited gains, hampered by rain and clouds, which have limited the air support.
Turkish warplanes struck the northern borders of Afrin, in tandem with heavy artillery shelling, and one civilian was killed, according to the Syrian Observatory for Human Rights, a Britain-based monitoring group.
Dozens of combatants and more than 2 dozen civilians have been killed so far since Turkey launched the offensive, the Observatory has said.
Turkey said the US had proposed a 30 km “safe zone” along the border with Syria.
“(But) in order for us to discuss the security zone or any other issue with the US, we have to reestablish trust,” Foreign Minister Mevlut Cavusoglu told reporters.
The Afrin operation has also triggered some concern in Germany, another NATO ally, where the caretaker government said on Thursday it would put on hold any decision on upgrading Turkey’s German-made tanks.
Turkey’s use of the Leopard 2 tanks in Afrin has fueled a debate about Berlin’s approval of arms exports.
A senior Kurdish official said on Thursday Syria’s main Kurdish groups would not attend a Syrian peace congress in Russia next week and that there could be no discussion of ending the war while the Turkish offensive continues.