"American citizens who choose to remain in Iraq are strongly urged to reconsider their decision in light of the significant threat posed by Iran-allied terrorist militia groups," the embassy wrote on social media.
Earlier on Saturday, the US embassy was damaged in an attack. The AP news agency said a missile hit a helicopter pad, while other media outlets reported drones.
The embassy has been repeatedly targeted by rockets and drones fired by Iran-linked militias. Attacks have also been directed at other American interests across Iraq.
There are no reports of anyone being injured in the latest attack.
