AirAsia agreed to order 175 Airbus A320 aircraft in 2005, with a delivery schedule running from December 2005 to October 2014, but earlier deliveries have been put back several times due to its overcrowded budget terminal.

"A key commercial reason for the (present) deferral... is to afford the company some flexibility to switch from its current order of the classic A320 to a new generation A320 aircraft which is more fuel efficient when such aircraft come into production in the near future," it said in a filing with the local bourse Friday.

"Despite the deferral, AirAsia will nevertheless be taking delivery of 14 aircraft in 2012," it added.

"This will enable the company to support the growth of its joint ventures in the Philippines as well as Vietnam while continuing to support existing affiliate airlines."

The company also said that the number of planes delivered in 2015 would accordingly increase from 9 to 19 aircraft, with no penalties payable for revising its delivery schedule.

In August the budget airline deferred delivery of seven aircraft by four years to 2015 due to space constraints at its Kuala Lumpur terminal.

In 2009, the Malaysian government vetoed AirAsia's ambitious plan to build its own 460-million-dollar airport far from the Kuala Lumpur International Airport (KLIA) in a bid to improve standards and lower operational costs.

However, it is now relying on Malaysia Airports Holdings, which runs KLIA, to build a new budget terminal that is scheduled for completion by March 2012.

AirAsia, which was launched in 2001 with just two planes, is now the region's fourth-biggest carrier with 25 million passengers a year.