Uh oh, this can't be good. 

Qatar Airways announced Wednesday that delivery of its first Airbus A350-900 XWB, originally planned for this weekend, has been postponed. No new date for the delivery or reasons for the delay were given.

It has to be something pretty substantial for Airbus and Qatar Airways not to reschedule or give a reason for the delay. The two have had a fractious relationship, with the airline and manufacturer squabbling in the past over the quality of interior finishes on A380s delivered earlier this year. This latest setback will do nothing to help repair the relationship.