WASHINGTON: The United States has ordered non-essential US embassy staff and their families to leave Saudi Arabia, the State Department said on Wednesday, as the kingdom comes under sustained deadly attacks by Yemen's Houthis.

"Iranian-supported Houthis have increasingly engaged in hostilities against Saudi Arabia, including attacks on civilian airports and other critical infrastructure resulting in civilian casualties and severe travel disruptions," State Department spokesman Tommy Pigott said in a social media post explaining the measure.

"The safety and security of Department personnel and their families remain our highest priority," he added.

A diplomatic source in the Middle East told AFP that some families of US embassy personnel were also being withdrawn from the United Arab Emirates, Jordan, Qatar and Bahrain, but Pigott stressed that Wednesday's order applied only to the departure of non-emergency embassy staff and their families in Saudi Arabia.