The U.S. has advised some personnel to leave the military's Al Udeid Air Base in Qatar after Iran threatened retaliatory strikes if Washington intervenes to protect Iranian protesters, according to a news report.

Three diplomats told Reuters about the advisement for the U.S.'s largest base in the Middle East, which houses around 10,000 troops.

The U.S. embassy in Doha did not have an immediate comment, and Qatar's Foreign Affairs Ministry did not immediately respond to Reuters' request for comment.

"It's a posture change and not an ordered evacuation," one of the diplomats told Reuters. The person said he was not aware that a specific reason had been given for the posture change.

A senior Iranian official told Reuters earlier Wednesday that Iran warned regional countries that it would strike U.S. military bases in those countries in case of a U.S. attack.

"Tehran has told regional countries, from Saudi Arabia and UAE to Turkey, that US bases in those countries will be attacked if the US targets Iran... asking these countries to prevent Washington from attacking Iran," the official told Reuters.

President Trump’s warnings to Iran have included threats of military force. He also warned Iran to not retaliate against the U.S., saying that if it did so, the U.S. would respond at levels “never seen before.”