In a remarkable announcement late Sunday, October 6 night, the White House said that United States forces in northern Syria would move aside in advance of a planned Turkish military offensive.

The move marks a major shift in US foreign policy and effectively gives Turkey the green light to attack US-backed Kurdish forces. The group, long considered as among Washington's most reliable partners in Syria, has played a key strategic role in the campaign against Isis in the region.

Following a phone call between US President Donald Trump and Turkish President Recep Tayyip Erdogan, the White House said that Turkey would soon begin a military offensive and US forces would not be involved in the operation.

"Turkey will soon be moving forward with its long-planned operation into Northern Syria," a statement said. "The United States Armed Forces will not support or be involved in the operation, and United States forces, having defeated the ISIS territorial 'Caliphate,' will no longer be in the immediate area."

The White House added Turkey would now be responsible for all captured ISIS fighters who are currently being held by US-backed Kurdish forces in northern Syria.

As of last month, the US said about 1,000 US troops were operating in northeastern Syria. Sunday's statement did not specify if this constituted a full withdrawal of personnel from the country.