Qatar Airways, a key customer for rivals Airbus and Boeing, said Monday it was disappointed at repeated delays in new aircraft and was losing confidence that either firm can deliver on time. Qatar Airways chief executive Akbar Al Baker said a two-year delay in the long-haul Airbus A350 left him \"very disappointed\" and frustrated as the airline tries to keep its ambitious expansion plans on track. \"Frankly, we are losing confidence in the manufacturers,\" he said, having suffered similar delays with Boeing\'s 787 Dreamliner, the direct competitor of the A350. Baker, when asked about possible cancellation of orders following delays, said: \"I don\'t want to talk about cancellation\" but was clearly angry at the latest turn of events where the airlines have few other options. On Sunday, Airbus confirmed two-year delays on two versions of the A350 to take on suggestions from clients, including for one of the planes to be able to fly further. The A350 XWB long-haul twin-jet is designed with mostly lightweight composite materials and is aimed directly at Boeing\'s 777 and 787 Dreamliner. Earlier Monday, Qatar Airways announced orders for six Boeing 777-300s worth $1.7 billion, continuing its policy of buying from both groups to avoid over-reliance on one. Baker said at the announcement ceremony that he could not comment directly on the changes to the A350 programme until he had a proper briefing from Airbus, with the plane effectively still on the drawing board. \"It is still a paper airplane. The proof of the pudding is in the eating and the 777 is already flying ... I do not like to talk (about it) ... at the moment until I\'m properly briefed by Airbus,\" he said. Airbus\' chief operating officer Fabrice Bregier said on Sunday the company planned to equip the A350-1000 with more powerful Rolls Royce engines to extend the plane\'s range. The company said it wanted to respond to demands from clients that would allow the A350-1000 to compete more directly with Boeing\'s 777-300ER, the plane ordered by Qatar Airways on Monday. Airbus\' commercial director John Leahy said: \"If you ask for improvements, you should expect delays.\" The delays will mainly affect Gulf customers who are the A350-1000\'s main clients. More than 570 A350s of all versions have already been ordered by 36 airlines. The company said the delays to the 800 version were down to clients who had asked that the 900s be delivered first.