European commercial aircraft builder Airbus said aircraft leasing company International Lease Finance is buying 20 of its future wide-bodied A350 aircraft in a deal potentially worth over US$3.29 billion on the basis of Airbus' catalogue prices.

ILFC had originally ordered 16 aircraft based on a first design for the A350 that Airbus scrapped in 2006 as the plane didn't offer airlines competitive facilities compared with Boeing's 787 Dreamliner.

ILFC is the world's leading commercial aircraft leasing company and is Airbus' biggest customer.

ILFC has signed up for the A350-800 and A350-900 versions of the aircraft, with the possibility of switching to the larger A350-1000 version.

The ILFC contract brings total orders for the A350 to 196 from nine customers.

Airbus is still in the process of deciding on suppliers for the aircraft, which will enter service with airlines in 2013.