Baghdad, Iraq - President Donald Trump's administration has ordered American citizens in Iraq to leave immediately as violence escalates across the Middle East due to the US and Israel's unprovoked war on Iran.

An alert was sent out by the US Embassy in Baghdad on Saturday, ordering American citizens to immediately leave Iraq due to the threat of pro-Iranian militias in the country.

"Iran-aligned terrorist militias have repeatedly attacked the International Zone in central Baghdad," the US Embassy and Consulate in Iraq warned in an alert that was updated on Sunday morning. "The International Zone remains closed."

The embassy warned that there have been repeated attacks on the Erbil International Airport and the Consulate General in Erbil, Iraqi Kurdistan. On Saturday, the US Embassy in Baghdad was hit by a drone strike.

"Iran and Iran-aligned terrorist militia groups pose a significant threat to public safety in Iraq," the statement read. "There have been attacks against US citizens, U.S. interests, and critical infrastructure."

"Iran-aligned terrorist militias have also attacked hotels frequented by foreigners and other facilities with US ties throughout Iraq," the embassy wrote, noting that the US has issued a Level 4 "Do Not Travel" advisory.

"Americans face the risk of kidnapping, and individual Americans have been targeted. Iran-aligned terrorist militias may impede Iraqi authorities' ability to respond effectively in an emergency."

The US-Israeli war on Iran has seen hundreds of civilians killed, many of them children, and has spread to neighboring countries as Tehran retaliates, while also virtually halting all traffic through the Strait of Hormuz, a crucial waterway for oil transit.