The deal for the MAX jets is valued at $5.67 billion at list prices, though discounts are common in large orders. WestJet has an option to buy 22 more MAX 10s.

WestJet, owned by private equity firm Onex Corp, said it will now accept delivery of "no fewer than 65 aircraft" in the next six years, with at least 50 being 737-10 jets.

(Reporting by Aishwarya Nair in Bengaluru)