Qatar operates an all-Airbus fleet

The �1.7bn deal will see Qatar buy two Airbus A380s with options for two more, as well as two long-range A340-600s with options for a further eight.

The contract was signed at the Dubai Air Show, and follows a memorandum of understanding agreement in June.

Qatar, which already has an all-Airbus fleet of 27 aircraft, has chosen Rolls Royce Trent engines to power the first of the two A340-600s.

It has not yet decided upon the engines for the A380s.

'Landmark'

Noel Forgeard, president and chief executive of Airbus, said: "This is another landmark in Airbus' success in the region, where Airbus has held a 60% market share over the past 20 years,"

Boeing, Airbus' American arch-rival, said losing the Qatar contract would not dent the strength of its position in the Middle East.

The company's Mark Baughman said: "We have a solid strategy going forward for the Middle East and beyond."

Airbus said earlier on Tuesday that it was "gathering information" to press for possible EU action against the United States over alleged violations by Boeing of international agreements on government funding of civil aviation projects.

Airbus is unhappy that some of Boeing's Japanese partners have allegedly benefited from state support.