MANILA - South Korea will transfer an ageing Pohang-class anti-submarine warship to the Philippines this year in return for just $100, the defense department said on Thursday, boosting its capability to patrol vast maritime borders.

Outside the United States, its former colonial master and long-time security ally, South Korea has been largest source of Philippine military hardware, from fighters and patrol ships to armoured vehicles and army trucks.

Manila received two FA-50 light fighters from Seoul on Wednesday and two more will be delivered next month to complete the 12 aircraft, 18 billion peso ($359 million) deal.

The Philippines has expressed interest to acquire six more similar planes.

"We are hoping to receive the vessel within the year," defense spokesman Arsenio Andolong said of the warship.

"The transfer will be in the form of a donation. We will pay a token $100, but the corvette will still undergo refurbishment."

He said he has no idea how much the Philippines would need to spend to repair and restore the warship.

Andolong said the Philippines may acquire up to three such warships, which Seoul is replacing with newer and faster vessels.

"This may be an old ship but it will definitely enhance our capability to patrol our waters and perform counter-terrorism measures," he added.

South Korea has donated a lot of military hardware to the Philippines and has expressed gratitude for Manila's role in the 1950-53 Korean War.