OTTAWA (Reuters) - Canada on Wednesday became the latest nation to ground Boeing 737 MAX aircraft, citing potential safety concerns after an Ethiopian Airlines Boeing MAX crashed on Sunday, killing 157 people.

The move means the United States is now the only major country where the planes are now operating.

Canadian Transport Minister Marc Garneau told a news conference that Ottawa would stop 737 MAX 8 and 9 jets from leaving, arriving in or flying over Canada.

“This safety notice is effective immediately and will remain in place until further notice,” he said, adding he had decided to act after receiving fresh information earlier in the day.

The ban is notable, since Canada usually works very closely with the U.S. Federal Aviation Administration (FAA). Garneau said there had been “absolutely no political pressure” from Washington after Canada informed it of the grounding.

Satellite data suggested similarities between the flight profiles of the Ethiopian jet and that of a Lion Air plane of the same type that crashed in Indonesia last year, he said. Both planes crashed shortly after takeoff.

“This is not conclusive, but it is something that points possibly in that direction and at this point we feel that threshold has been crossed and that is why we are taking these measures,” he said.

A U.S. official told Reuters the FAA was aware of the satellite data Garneau had cited, but called it inconclusive.

Air Canada, which operates 24 Boeing 737 MAX jets, said it was working to re-book passengers as quickly as possible. Rival WestJet Airlines Ltd, which operates 13 of the jets, said it would comply with the order.

The Air Canada Pilots Association, which represents more than 4,000 commercial pilots, said the decision was “important to ensure continued public confidence in aviation”.