The two leaders spoke on the day Erdogan announced that Turkey would extend its military operation to the Syrian town of Manbij, a move that could bring Turkish forces into possible confrontation with those of their NATO ally the United States.
“President Trump relayed concerns that escalating violence in Afrin, Syria, risks undercutting our shared goals in Syria,” the White House said in a statement.
Those goals include defeating Islamic State and bringing more than 100,000 Syrian refugees back to their home country, Trump told Erdogan.
“He urged Turkey to deescalate, limit its military actions, and avoid civilian casualties and increases to displaced persons and refugees,” it said. “He urged Turkey to exercise caution and to avoid any actions that might risk conflict between Turkish and American forces.”
Erdogan told Trump in the call that the United States must halt weapons support to the Syrian Kurdish YPG militia, Erdogan’s office said.
Turkey’s air and ground “Operation Olive Branch” in the Afrin region of northern Syria is now in its fifth day, targeting YPG fighters and opening a new front in Syria’s multi-sided civil war.
The operation intended to “purge terrorist elements” from Afrin for Turkey’s national security and was conducted on the basis of international law, the Turkish president’s office said in a statement.
The United States has around 2,000 special forces troops in Syria who were deployed in March.
The Turkish incursion could threaten US plans to rebuild a large area of northeast Syria beyond President Bashar Assad’s control.
Turkey sees the YPG — the most powerful faction within the US-backed Syrian Democratic Forces rebel group — as an extension of a Kurdish group that has waged a decades-long insurgency in southeastern Turkey. Ankara says it will not allow the Kurdish fighters to control a strip of Syrian territory on its southern border.
“President Trump also expressed concern about destructive and false rhetoric coming from Turkey, and about United States citizens and local employees detained under the prolonged State of Emergency in Turkey,” the White House said.
The United States has expressed concern over the detention of locals employed at diplomatic missions in Turkey and the fate of US citizens, including a Christian missionary, detained since a failed coup in July 2016.