Vietnamese low-cost operator VietJet Air has tentatively signed to acquire 62 A320-family aircraft and take purchase rights on 30 more.
The operator also intends to lease a further eight from third parties, bringing its potential commitment to 100 Airbus single-aisle jets.
VietJet Air's memorandum of understanding, disclosed in the week of Beijing's Aviation Expo, covers 42 A320neo aircraft plus 14 baseline A320s and six A321s.
The private carrier, which started flying in late 2011, has recently acquired its ninth leased A320.
VietJet Air managing director Luu Duc Khanh says the type has "proven to be extremely efficient in service".
No engine selection or delivery dates have been given.