Syria's dominant Kurdish party on Wednesday called on the U.N. Security Council to act quickly to ensure the safety of Kurdish-controlled territories in the country's north, including an enclave that Turkey has threatened to attack.
Turkey's President Recep Tayyip Erdogan has said he will launch a military offensive in the coming days against territories controlled by the dominant Syrian Kurdish militia in northwestern and eastern Syria, and in particular the enclave of Afrin, where an estimated 1 million people live.
Turkey views the US-backed Syrian Kurdish forces as terrorists, and an extension of the Kurdish insurgency raging in its southeast. It has criticized the U.S. for extending support and arming the Kurdish forces as part of the campaign that drove the Islamic State group from large parts of Syria.
The Kurdish militia, which forms the backbone of the U.S.-backed Syrian Democratic Forces, now controls nearly 25 per cent of Syrian territory. It is the U.S.-led coalition's chief ally in the campaign against IS in Syria.
The U.S.-led coalition recently said it is planning a 30,000-strong Kurdish-led border force, further angering Turkey.
Turkish Foreign Minister Mevlut Cavusoglu said he told U.S. Secretary of State Rex Tillerson that those plans were a "perilous" step that would "seriously endanger ties." The two met in Vancouver Tuesday.
"Such a development would damage Turkish-American ties in an irreversible manner," the state-run Anadolu Agency quoted Cavusoglu as saying on Wednesday.
Erdogan said the imminent military operation is to "purge terror" from near its borders. Along with Afrin, Erdogan has also threatened Manbij, a town the Kurdish-led SDF seized from IS in 2016.
The Kurdish Democratic Union Party, or PYD, the political arm of the main Kurdish militia, said that if Turkey launches an operation against Afrin, the world will bear responsibility for the lives of people residing there. The PYD called on the Security Council to "move immediately" to ensure the security of Kurdish-controlled areas in Syria.
"Such a responsible behaviour will lead to the desired result in finding a resolution for the Syrian crisis," the PYD said in a statement.
The Syrian government of President Bashar Assad has meanwhile accused the SDF of being "traitors" for co-operating with the United States.
On Monday, Erdogan accused the United States of creating an "army of terror" in Syria along the border with Turkey, a reference to the plans for the border force. He vowed to crush the border force and called on NATO to take a stand against the United States, a fellow ally.
Meanwhile, Syrian activists said Turkish military activities near the borders with Afrin have continued, as well as shelling of the outskirts of the town. Tanks amassed near the border with Syria, while Turkish media reported that medical personnel in Kilis, a Turkish town across the border from Afrin, were asked not to take leave, apparently in anticipation of military operations.
Turkey's private Dogan news agency quotes Turkey-backed Syrian rebels as saying they are awaiting Turkish orders to launch the Afrin operations. It says some 3,000 fighters are ready to participate in operations against Afrin and Manbij.