Qatar Airways (search) gave a big boost to European planemaker Airbus on Monday, choosing its future mid-sized jet over a more established rival from Boeing as part of a mammoth $15 billion order plan.

Doha-based Qatar said it was close to signing a deal to buy up to 60 of Airbus's new A350 (search) jets worth $10.6 billion, and would also buy at least 20 of Boeing Co's larger 777 planes for around $4.6 billion.

The massive order revived what was threatening to be a lacklustre Paris Air Show (search) which has been dominated by a trade spat over planemaker subsidies rather than big deals.

It gives a big shot in the arm to Airbus as it tries to build up enough orders to proceed with the A350, a rival to Boeing's 787 model which has already racked up over 250 potential orders. Airbus hopes to give the A350 a formal go ahead by the end of September.

Qatar, one of the world's fastest growing airlines, plans to triple in size over five years as it seeks to capitalize on a boom in development and tourism in the oil-rich Middle East.

"Our passenger target by 2015 will be around 15 million and we should be having somewhere in the region of 90 to 105 aeroplanes," Qatar Chief Executive Akbar Al Baker told Reuters.

"The Airbus A350 will be the ultimate choice for the future of the airline."

The order puts Airbus closer to achieving its target of 100 orders for the future mid-sized aircraft by the end of this week's show, the world's biggest.

"I always stand by what I say -- 100," Airbus's chief salesman John Leahy told Reuters, asked whether he stood by his recent forecast of 100 total orders by the end of the show.

Airbus has already sold 10 of the planned A350 aircraft, due to start deliveries in 2010, to Air Europa and another 20 to US Air in return for a $250 million loan.

Middle Eastern airlines have dominated orders at recent international airshows as rapid development, including a new airport for the tiny Gulf Arab state of Qatar, and growing tourist numbers drive passenger demand.

Dubai-based rival Emirates disappointed last week by saying it did not plan to make a major order announcement at the show.

The mix of Airbus A350-800 and A350-900 planes would be delivered as part of a fleet upgrade program between 2010 and 2015, Qatar said.

The Boeing 777-300ER (search) model was likely to account for around half of the order with the U.S. aerospace group with delivery scheduled between 2007 and 2010.

Al Baker told Reuters he expected the orders to be signed within "days" or "weeks." None of the new orders would replace existing aircraft orders, he said.

General Electric Co. will supply engines for all the planes.

Meanwhile, the European Unionand United States on Monday delayed the immediate launch of World Trade Organization (WTO) probes into how Boeing and Airbus are financed, officials in Geneva said.

Blocking the creation of panels at the first request is stand practice in WTO disputes and the move had been widely predicted, as the world's two aerospace giants circle each other in a stand-off over government subsidies.