UPDATE 1-Qatar to make Airbus order at UK air show

(Adds background on Qatar purchases)

NEW YORK, July 9 (Reuters) - Qatar Airways plans to hold a joint press conference with EADS (EAD.PA: Quote, Profile, Research) unit Airbus next week at Britain's Farnborough International Airshow, likely signaling a major airplane order.

The company did not indicate what the press conference concerned, but an industry source said the Gulf-based airline was expected to announce a large plane order at the show.

Airbus, which competes with Boeing Co (BA.N: Quote, Profile, Research) in the global airliner market, was not immediately available to comment.

Qatar Airways, one of the leading plane-buyers among quickly expanding Middle Eastern carriers, has traditionally been a staunch Boeing customer. Last year it ordered 30 of Boeing's new 787 Dreamliners and has 27 of its larger 777s on order.

At last year's Paris air show, Qatar confirmed a previously announced order for 80 new Airbus A350 XWB models -- which will compete with the 787 -- and three additional A380 superjumbos, worth about $17 billion in total. (Reporting by Bill Rigby; Editing by Lisa Von Ahn)