Turkey will buy a first batch of two F-35A Joint Strike Fighters as a sign of its commitment to the troubled US-led program.

Turkey will buy a first batch of two F-35A Joint Strike Fighters as a sign of its commitment to the troubled US-led program, the government's defense procurement agency said on Thursday.

A statement said the government had authorized the order to meet the future needs of the Turkish air force for next-generation fighter planes.

Turkey has long planned to purchase about 100 jets to replace its F-4 and F-16 fleet, but the increasing costs have hampered the acquisitions.

The Joint Strike Fighter, manufactured by Lockheed Martin, is the Pentagon's most expensive weapons program ever.

Its cost has jumped to about 385 billion dollars, and the price of each plane is now well over 100 million dollars. US officials said last month that it has encountered a spate of technical problems expected to delay production still further.

However at the same time Japan said it had chosen the F-35 for its next-generation mainstay fighter, ordering 45 of the aircraft in a deal worth around $4.7 billion.

The Pentagon plans three versions of the plane: the standard F-35A that would replace the F-16 fighter, the F-35C designed to land on naval carriers to replace the F-18 and the F-35B vertical take-off model that would supplant the Harrier aircraft flown by US Marines.