WASHINGTON (AP) — The White House said Sunday that Turkey will soon invade Northern Syria, renewing fears of a slaughter of Kurdish fighters allied with the U.S. in a years-long campaign against the Islamic State group.

For months, Turkish President Recep Tayyip Erdogan has been threatening to launch a military assault on the Kurdish forces in Northern Syria, many of whom his government considers terrorists. The Kurdish forces bore the brunt of the U.S.-led campaign against Islamic State militants, and Republicans and Democrats have warned that allowing the Turkish attack would send a troubling message to American allies across the globe.

U.S. troops “will not support or be involved in the operation” and “will no longer be in the immediate area,” in Northern Syria, White House press secretary Stephanie Grisham said in an unusual late-Sunday statement that was silent on the fate of the Kurds.

It was not clear whether that meant the U.S. would be withdrawing its 1,000 or so troops completely from northern Syria.

The announcement came after a call between President Donald Trump and Erdogan, the White House said.

In December, Trump announced he was withdrawing American troops from Syria but was met with widespread condemnation for abandoning Kurdish allies to the Turkish assault. The announcement prompted the resignation in protest of then-Defense Secretary Jim Mattis, and a coordinated effort by then-national security adviser John Bolton to try to protect the Kurds.

The White House statement Sunday said Turkey will take custody of foreign fighters captured in the U.S.-led campaign against the Islamic State group who have been held by the Kurdish forces supported by the U.S.

Ambassador James Jeffrey, the State Department envoy to the international coalition fighting the Islamic State group, and Trump have said there are about 2,500 foreign fighters captured in the fight against the Islamic State that the U.S. wants Europe to take.

Trump has repeatedly demanded that European countries, particularly France and Germany, take back their citizens who joined the militant organization.

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