Budget carrier AirAsia has ordered another 64 Airbus A320neos as well as a further 36 baseline A320s.
The deal confirms AirAsia as the undisclosed customer behind a deal for 100 A320s booked in November.
AirAsia had previously indicated that it was negotiating for 100 jets but that it had opted against a high-density Bombardier CSeries.
No delivery dates have been disclosed for the AirAsia jets, nor has an engine selection been given.
It takes AirAsia's overall Airbus orders to 264 A320neos and 211 regular A320s.
Airbus values the agreement, unveiled during an event at its UK plant at Broughton, at $9.4 billion at catalogue prices.