"Or they can listen to their commanders, who say that they will fight the Turkish forces - in which case we will have no choice but to stop them from disrupting our counter-Islamic State [Daesh] efforts", Altun said, according to The Washington Post. But the Turkish government views them as a terrorist insurgency linked to the Marxist Kurdistan Workers' Party (PKK).
Iran has voiced its opposition to any military action in Syria, saying a Turkish offensive on Syrian territory would result in widespread human and material damage. Erdogan, however, sees the Kurds as terrorists and a threat along Turkey s southern border.
Turkey's President Recep Tayyip Erdogan, for his part, confirmed that USA troops began pulling out of northern Syria as Ankara plans to launch an anti-terrorist operation against Kurdish forces in the area.
They will be based in the Turkish border town of Ceylanpinar, it said, across the border from the Syrian town of Ras al-Ain, with 14,000 of them gradually joining the offensive.
"Establishment of a safe zone/a peace corridor is necessary for giving a safe life to Syrians by contributing to the peace and stability of our region", a statement on the ministry's Twitter account said on Monday, Efe news reported.
Mr Trump said earlier this week the United States would step aside for an expected Turkish attack on Syrian Kurdish fighters, who have fought alongside Americans for years, but he then threatened to destroy the Turks' economy if they went too far.
Chief Pentagon spokesman Jonathan Hoffman said Tuesday that "Despite continued misreporting to the contrary", President Trump had over the last several days consulted with Defense Secretary Mark Esper and Chairman of the Joint Chiefs of Staff Mark Milley "regarding the situation and efforts to protect USA forces in northern Syria in the face of military action by Turkey".
Now that President Trump wants to withdraw U.S. troops from Iraq and Syria because he believes that ISIS no longer poses the existential threat to Western culture as it did when it first made its appearance on the political scene some years ago, it appears that he has given the green light to Turkey to finish the job.
If American troops are removed, the fear is that Turkey's military will move in.
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USA involvement in Syria has been fraught with peril since it started in 2014 with the insertion of small numbers of special operations forces to recruit, train, arm and advise local fighters to combat the Islamic State.
However, a Sputnik Turkey correspondent challenged the claims, suggesting that Turkish troops and vehicles had not yet crossed the Syrian border.
Senator Lindsey Graham vowed Wednesday that Congress will inflict a cost on Turkey for its offensive against Syria's Kurds as the usually loyal ally of President Donald Trump sharply criticized United States policy.
Later when expanding on his "off limits" tweet, Mr Trump said Turkey should "not do anything outside of what we would think is humane".
Earlier, Turkish television reports said Turkish jets had bombed Syrian Kurdish positions across the border from Turkey. "We are helping the Kurds financially/weapons!"
Turkey wants to create a "safe zone" cleared of a Kurdish militia that will also house some of Turkey's 3.6 million Syrian refugees.
Armed by the US and backed by American troops and firepower, the Kurdish-led forces put an end to IS territorial hold in the region - at the cost of thousands of Kurds killed in years of fighting.
"That surprises me that anyone would say that, because this is something that was discussed among senior leadership here at the White House, the State Department and the Pentagon".
Russia, Syrian President Bashar al-Assad's strongest foreign ally, said it was not told in advance by the U.S. or Turkey about any agreements they had about plans to pull American troops from the north-east, adding that it was watching the situation very closely.