The department also urged US citizens in these countries to monitor local media and the official US alerts to stay informed.

Earlier, the US Embassy in Kuwait said on Tuesday that it "will be closed until further notice," over the ongoing regional tensions.

"We have canceled all regular and emergency consular appointments. We will communicate when the embassy returns to normal operations," the embassy said through the US social media company X.

In its travel advisory for Iraq, the US mission in Baghdad also said the Department of State ordered non-emergency government employees "to leave Iraq due to security concerns."

"Because of security concerns, US government personnel in Baghdad are prohibited from using Baghdad International Airport," it added.

The developments came as the ongoing US-Israeli military campaign, launched against Iran on Saturday, has killed several senior Iranian officials, including Supreme Leader Ali Khamenei.

In response, Tehran has retaliated with drone and missile strikes targeting Israel, as well as several regional countries that are home to US assets.