Turkish leaders have pledged to launch a military offensive into northern Syria against the People's Protection Units (YPG), a Kurdish force that makes up the bulk of the SDF.

"We’ve been clear that the Syrian Democratic Forces should not be engaged militarily, and that would include the Kurdish component of the SDF," Palladino told a State Department press briefing.

Following a phone conversation with U.S. President Donald Trump, Turkish President Recep Tayyip Erdogan announced on January 15 that Ankara would create a 32-km buffer zone in northern Syria. The spokesperson for the Turkish presidency, Ibrahim Kalin, later said the security zone would be controlled by Ankara.

The buffer zone idea was originally proposed by U.S. President Donald Trump, but he threatened on Twitter to “devastate Turkey economically” if Ankara attacked the Kurds in Syria.

When asked about reports that the U.S. administration had asked France, Britain and Australia to form a force to create the buffer zone, Palladino said he had not been informed on the issue, "but talks are ongoing on many different levels right now", he said.

Relations between Turkey and the United States have suffered a series of setbacks in the last year over Syria, the arrest of each other’s citizens and Turkey’s planned purchase of Russian missile systems.

Reporter’s code: 50101