U.S. aviation officials urged flight crews operating over Belarus to exercise “extreme caution,” but stopped short of a ban on overflights of the region.

The Federal Aviation Administration on Friday issued a so-called notice to airmen in the wake of the forced diversion of an airliner carrying a political opponent of that nation’s government on Sunday.

The European Union’s air-safety regulator advised airlines to avoid Belarus airspace after the diversion of a Ryanair Holdings Plc flight.

The FAA notice applies to U.S. passenger flights, not cargo operations. The agency said it is continuing to evaluate the situation “and the potential for Belarus to repeat similar actions to what occurred on 23 May 2021 in the future,” it said.