The Philippines said Friday it will buy $524.7-million worth of aircraft from South Korea and Canada as part of a military upgrade amid territorial disputes with superpower neighbour China.

The contracts to be signed on March 28 will include the purchase of 12 FA-50 fighter jets from state-run Korea Aerospace Industries for 18.9 billion pesos ($417.95 million), Defence Undersecretary Fernando Manalo told reporters.

State-owned Canadian Commercial Corp. will meanwhile be contracted to supply eight Bell 412 combat utility helicopters worth 4.8 billion pesos, with the first three helicopters expected to be delivered next year, he added.

"This is significant because it will give our armed forces the minimum capability to demonstrate their ability to perform their responsibilities," he added.

The Philippines has embarked on a 75-billion-peso effort to upgrade its armed forces, particularly units tasked with patrolling disputed territory in the South China Sea.

These units are dwarfed by those of neighbouring China, which claims most of the area, including waters and islets much closer to the Philippines.

The Philippines has already acquired two refurbished frigates from the US coastguard as part of its military modernisation programme.

China said its coastguard on March 9 blocked two Philippine-flagged vessels approaching Second Thomas Shoal, which is guarded by a small group of Filipino marines but is also claimed by Beijing.

The shoal is part of the Spratlys, a chain of islets and reefs that sit near key shipping lanes, are surrounded by rich fishing grounds and are also believed to lie atop huge oil and gas reserves.

The Philippines has also accused the Chinese coastguard of firing water cannon blasts on January 27 at two Filipino fishing vessels off Scarborough Shoal, a rocky outcrop lies just 220 kilometres off the main Philippine island of Luzon.