UPDATE 1-Panama's Copa grounds planes as region's regulators stand by

Panama's Copa Holdings said on Wednesday it would suspend operations of its six Boeing 737 MAX 9 aircraft, the latest airline in the region to ground planes in the wake of Sunday's crash of an Ethiopian Airlines plane. The decision followed an order by the U.S. air regulator to ground Boeing 737 MAX jets, joining government regulators in Europe, China and other countries.

But even as regulators around the world have ordered the planes grounded, Latin America has largely left it up to carriers to make their own decisions. As of Wednesday night, regulators in Brazil, Argentina and Mexico, the largest air travel markets in the region, had not forced the grounding of planes. Argentina's state-run news agency Telam reported on Tuesday that South American regulators were discussing potential groundings, but said no decision was "imminent" and would be made by the countries as a group.

Brazil's chief federal prosecutor asked ANAC, the local regulator, on Wednesday to force the suspension of Boeing 737 MAX planes, but as of Wednesday evening no decision had been made. Copa operates Boeing 737 MAX 9 planes, which are of the same family but not the same model as the one involved in the Ethiopian Airlines crash. That was a Boeing 737 MAX 8, the same model that was involved in the October 2018 crash of a flight operated by Lion Air in Indonesia.

All three Latin American airlines that operate MAX 8 planes -- Brazil's Gol Linhas Aereas Inteligentes, Aerolineas Argentinas and Aeromexico -- grounded their planes following the crash. (Reporting by Elida Moreno in Panama City and Marcelo Rochabrun in Sao Paulo Editing by Dave Graham)