The additional military personnel will assist an alliance of Kurdish and Arab forces in the fight against Daesh.
The United States will send 200 additional troops to Syria to boost the ongoing offensive against Daesh in Raqqa, US Defense Secretary Ash Carter said on Saturday.
The 200 personnel, including special forces trainers, advisers and explosive ordnance disposal teams, will complement 300 US special forces already in Syria, Carter told Gulf policymakers in the Bahraini capital, Manama. The decision to send more troops comes days after President Barack Obama lifted restrictions on arms supplies to foreign and local forces allied with the US in Syria.
The deployment of additional US troops "had been anticipated for some time", CNN quoted a senior US defense official as saying.
"These uniquely skilled operators will join the 300 US special operations forces already in Syria, to continue organising, training, equipping, and otherwise enabling capable, motivated, local forces to take the fight to ISIL (Daesh)," Carter said in a speech.
"We're now helping tens of thousands of local Syrian forces to isolate Raqqa," Carter said, referring to the alliance of Kurdish and Arab fighters.
He said the coalition fighting Daesh in Iraq and Syria had to be prepared for "anything" as the battle had reached a "critical milestone."
Raqqa and the Iraqi city of Mosul are the last major urban centres under Daesh control, and recapturing the two cities would be a critical defeat for them.