PARIS--Qatar plans to buy 22 NH90 military helicopters from a consortium led by Airbus Group, as well as two MRTT airborne refueling tanker versions of the Airbus A330 jetliner, an official of the French Defense Ministry said Thursday.

A letter of intent for the order was signed at DIMDEX, a maritime defense trade show in the Qatari capital Doha, by Qatari officials and French Defense Minister Jean-Yves Le Drian. The order, if confirmed, is potentially worth some EUR2 billion, the official said.

The order comprises 12 TTH tactical transport versions of the NH90, as well as 10 frigate versions, the official said. The NH90 is a medium-size, twin-engine, multi-role helicopter manufactured by NHIndustries, a consortium that is 62.5% controlled by the helicopter division of Airbus Group. AgustaWestland, a unit of Italy's Finmeccanica SpA, has a 32% stake and Stork Fokker of the Netherlands the remaining 5.5%.

The Airbus MRTT has been ordered by the air forces of Australia, the U.K., the United Arab Emirates, Saudi Arabia and Singapore, and France has said it wants to buy 12 of the aircraft that can also be used to carry passengers and cargo in addition to their role as in-flight gas stations for military jets.

Separately, French defense and electronics systems group Thales SA said Thursday it has signed a memorandum of understanding with the Qatar armed forces to assist in the development of an optionally piloted airborne vehicle that would be a hybrid between a conventionally piloted aircraft and an unmanned aircraft system. The OPV-A would be able to fly without a pilot on intelligence, reconnaissance, surveillance and target acquisition missions, with the advantage that they can operate for longer periods and without the physiological limitations of a human pilot. However, it will also be designed to be flown by a pilot.

Terms of this development contract weren't disclosed.

Write to David Pearson at david.pearson@wsj.com

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