Turkey to act in Syria if US does not withdraw 'terror' border force backing

Tanks have 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.

The US-led coalition fighting the Islamic State group said on Sunday that they were working with the Syrian Democratic Forces (SDF) to create a 30,000-strong border security force in northern Syria, a statement that drew sharp condemnation from other countries.

Washington denied such plans and told Reuters that "some people misspoke."

Ankara is fiercely opposed to the SDF, which is dominated by the Kurdish People's Protection Units (YPG) – considered by the Turkish government to be a "terrorist" group.

Turkey views the YPG as an extension of PKK, the Kurdistan Workers' Party, and described the force as a "terror army". The PKK is considered a terrorist group by the European Union, Turkey and the United States.

Read also: A Turkish attack on Kurds will further destabilise Syria's northwest

The coalition says the force, expected to reach 30,000 in the next several years, is a key element of its strategy to prevent the resurgence of the Islamic State group in Syria and would be deployed along Syria's border with Turkey and Iraq.

Iran also joined Turkey in hitting out at the proposed plans, saying that it will only cause more instability and "add flames of fire" in an already war-torn country.

Syrian President Bashar al-Assad responded by vowing to crush the new "traitor" force and drive US troops from Syria and powerful ally Russia called the plans a plot to dismember Syria and place part of it under US control.

Erdogan has long threatened an operation against the YPG's enclave in Afrin but has stepped up his threats in recent days, saying Ankara troops will clear it of "terrorists".

On Tuesday, he warned an assault on Afrin could take place "tomorrow, (or) the day after, (or) within a short period".

In response to Erdogan's threats, Kurdish fighters have said that their forces are ready to fight the Turkish army.

"We will foil Erdogan's filthy plans. We will turn those plans to major victories for the people of the region, the Kurdish, Syrian, and Turkish people," YPG chief, Sipan Hemo pledged.

Rex Tillerson, US Secretary of State however, has denied that Washington has any intention of building the force, saying the issue had been "misportrayed, misdescribed". 

"Some people misspoke. We are not creating a border security force at all," Tillerson told reporters.

"I think it's unfortunate that comments made by some left that impression," he said, without giving details. "That is not what we're doing."

Turkish officials had been informed that US intentions were only "to ensure that local elements are providing security to liberated areas" added Tillerson.

An earlier statement by the Pentagon described the training as "internally focused" on Syrian fighters to aid in the fight against IS' resurgence.

"We are keenly aware of the security concerns of Turkey, our coalition partner and NATO ally. Turkey's security concerns are legitimate," it said.