The Pentagon already had begun taking measures to strengthen its firepower in the Middle East and protect U.S. bases there.

Iran launched retaliatory strikes Qatar's Al-Udeid airbase, a critical U.S. military hub for CENTCOM operations, following American attacks on Iranian nuclear sites.

Qatar's prime minister said on Tuesday relations with Iran have been scarred by an Iranian missile volley at a U.S. airbase in the Gulf Arab state, but that he hoped ties would eventually "come back to normal".