AlexeyPetrov/iStock(WASHINGTON) — The Federal Aviation Administration has prohibited “all U.S. carriers and commercial operators” from flying over the Persian Gulf and Gulf of Oman, near Iran, in the wake of the country shooting down an unmanned drone early Thursday.

The FAA announced the decision, called a notice-to-airman, or NOTAM, alert, late Thursday.

“All flight operations in the overwater area of the Tehran Flight Information Region (FIR) (OIIX) above the Persian Gulf and Gulf of Oman only are prohibited until further notice due to heightened military activities and increased political tensions in the region, which present an inadvertent risk to U.S. civil aviation operations and potential for miscalculation or mis-identification,” the FAA said in a press release.

#FAA issued #NOTAM warning pilots that flights are not permitted in the overwater area of the Tehran Flight Information Region until further notice, due to heightened military activities and increased political tensions. https://t.co/BQ2GOeFSEn pic.twitter.com/4t1OWEzkYZ

— The FAA (@FAANews) June 21, 2019

The NOTAM applies to all U.S. air carriers and commercial operators, but does not apply to U.S.-registered planes for foreign carriers.

Sources told ABC News President Donald Trump ordered a military strike on Iran late Thursday, but then reversed course after a plan was already underway.

Trump’s reason for changing course was unclear, but the reversal was against the advice of Secretary of State Mike Pompeo and National Security Adviser John Bolton.

Tensions were elevated to a new level on Thursday morning when Iran shot down an unarmed RQ-4A Global Hawk drone that the U.S. said was flying in international airspace over the Gulf of Oman near the Strait of Hormuz. Iran has taken issue with that categorization, saying the drone was flying over its airspace when it was downed.

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