The two A340-500s will be the last examples of the four-engined jetliner to be delivered brand-new from their French factory and had previously been earmarked for struggling Indian carrier Kingfisher Airlines (KING.NS), industry sources say.

Airbus has already halted production of the A340, which came out in 1993 just before changes in engine design and regulations allowed Boeing to develop its rival 777 with two engines instead of four, allowing airlines to fly many routes at a lower cost.

Airbus said the 282-seat A340-500 aircraft, each with a range of 16,670 km (9,000 nautical miles), had been sold to AJW Capital Partners, an aviation services group based in the UK.

They will be placed into commercial service with an unidentified airline early next year, it said in a statement.

Airbus declined to comment on the background to the sale, but industry sources have previously said the only two A340s remaining for sale had originally been built for Kingfisher.

They were most recently listed by Airbus as waiting for delivery to unidentified private customers.

Once considered Airbus's most glamorous jet, the slender A340 boasted "four engines for long-haul" and versions of the passenger plane once held records for endurance and the biggest passenger jet by fuselage length, both now held by Boeing.

In its heyday, the A340 was feted when Virgin Atlantic boss Richard Branson asked the late Princess Diana to name one the "Lady in Red," but caused blushes at Airbus a decade later when another crashed into a concrete barrier during ground tests.

More recently Airbus and even its rival Boeing have been buying A340s back from airlines as trade-ins to facilitate sales of more efficient two-engined aircraft.

The only four-engined passenger jets left in their catalogues are the larger 525-seat Airbus A380 superjumbo and the latest 467-seat version of Boeing's jumbo jet, the 747-8.

Halting production of the A340 will however benefit its smaller cousin, the A330, the European company's best-selling long-haul jet which generates significant cash for Airbus.

Because both models share the same type of wing, engineers have found a way to improve the A330's performance by redesigning the place reserved for the A340s two extra engines.

The changes are designed to gird the A330 for a new round in the perennial battle for sales between Airbus and Boeing as the U.S. company prepares to launch a stretched version of its 787 Dreamliner -- dubbed the "A330-300 killer" by Boeing supporters.

Airbus insists the A330 has a solid future especially as a cross-regional jet within Asia, a fast-growing travel market. (Reporting by Tim Hepher; Editing by Christian Plumb)

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