Dubai's Emirates airline has delivered a blow to European aerospace group Airbus, cancelling an order for 70 new-generation A350 airliners.
The long-distance aircraft, due to go into service this year, is the Airbus flagship project of the moment to compete with the Boeing 787 which has been flying since 2011.
The size of Wednesday's cancellation is the largest by a prestigious customer for a civil airliner.
Analysts estimate it represents about a tenth of the aircraft maker's 2014 orders.
Airbus said the cancellation followed an order placed by Emirates at the Dubai air show in November for an extra 50 A380 superjumbo planes.
The cancellation decision was made following "ongoing discussions with the airline in light of their fleet requirement review", Airbus said.
The deal was said to be worth $16.5bn (12bn euros) when it was announced in 2007, but the head of Airbus's sales division, John Leahy, said that customers were already interested in taking up the cancelled aircraft.
"It's not good news commercially but it has no impact financially," Leahy said.
In London, aero-engine maker Rolls-Royce warned that the decision would cut the value of its order book by 2.6bn pounds ($4.3bn, 3.2bn euros).
The cancelled planes were to be delivered from 2019.