BEIRUT, Lebanon — The United States began withdrawing its troops from Syria on Friday, an American military spokesman said, a first step in President Trump’s plan to remove American forces from one of the Middle East’s most complex battlefields.
The surprise announcement came in a statement from Col. Sean Ryan, the spokesman for the United States-led coalition against the Islamic State. Colonel Ryan said the coalition had “begun the process of our deliberate withdrawal from Syria,” adding that he would provide no further information about “specific timelines, locations or troop movements.”
The withdrawal of the roughly 2,000 American troops posted in northern and eastern Syria threatened to hinder the enduring defeat of the Islamic State and unleash a potentially violent scramble between the other forces in Syria to fill the void.
Mr. Trump has made no secret of his desire to bring the troops home, saying that they were sent to fight the Islamic State and that their mission has nearly been accomplished, but his plan to do so has become muddled.
Mr. Trump said last month that he wanted the troops out in 30 days. But after discussions with others in his administration, the timeline was lengthened, while diplomats sought to find a way to protect the United States’ Kurdish allies from a Turkish attack and to get Turkey to take over the fight against the jihadists.
As recently as Sunday, Mr. Trump’s national security adviser, John Bolton, said that the pullout was conditional on circumstances that could leave American forces there for months or even years.
The United States had sent forces to Syria to work with local, Kurdish-led militias to fight the Islamic State, which had established a self-declared caliphate that spanned the border between Syria and Iraq.
As the militants were pushed back, the zone of American influence grew to include roughly one-quarter of Syria’s territory, where the militias set up local councils to conduct basic governance.
The Syrian government and its Russian and Iranian allies want the territory back for several reasons: its oil deposits; its agricultural land; reopening the border with Iraq; and reunification of the country, which has been shattered by a war that began in 2011.
Turkey also has interests in the area and sees the primary Kurdish militia there as a national security threat. It has sent its troops to the Syrian border and threatened to send them into Syria to fight the Kurds.
A United States withdrawal would make it easier for all those forces to make moves into the area, perhaps bringing them into conflict.