FILE PHOTO: Boeing employees are pictured in front of a 737 MAX 8 produced for Southwest Airlines as Boeing celebrates the 10,000th 737 to come off the production line in Renton, Washington, U.S., March 13, 2018. REUTERS/Jason Redmond

CHICAGO (Reuters) - The Southwest Airlines pilots union said on Wednesday that it remained confident in Boeing Co’s 737 MAX even after Canada became the latest country to ground the jet.

Southwest has the largest 737 MAX fleet in the world with 34 aircraft.