The reinforcements will come from the 82nd Airborne Division's Global Response Force, which already supplied several hundred extra troops to the region earlier this week as tensions grew over an attack on the US embassy in Baghdad.

A Defense Department spokesperson said that the 82nd Airborne's Immediate Response Force brigade had already been notified earlier this week that they could be sent to the region.

"The brigade will deploy to Kuwait as an appropriate and precautionary action in response to increased threat levels against U.S. personnel and facilities, and will assist in reconstituting the reserve," the official said.

The move came as tensions soared following the US killing of Qasem Soleimani, the head of the Islamic Revolutionary Guard Corps' foreign operations arm, whom Washington said was behind attacks on US facilities in Iraq in recent months.