The Philippines has asked a United Nations body to formally recognise the extent of its undersea continental seabed in the South China Sea, where it would have the exclusive right to exploit resources, the Department of Foreign Affairs has said, in a move that rejects China’s vast territorial claims to the region.

The Philippine government submitted information to the UN Commission on the Limits of the Continental Shelf on the extent of its undersea shelf in the South China Sea, off western Palawan province, after more than a decade and a half of scientific research, the department said on Saturday.

China did not immediately comment but it will likely contest the Philippine move.

The undersea region where the Philippines seeks to formally establish its sovereign rights under the UN Convention on the Law of the Sea, or UNCLOS, covers the Spratlys, a chain of islands, islets, reefs and atolls that has been fiercely contested over the years by China, the Philippines, Vietnam, Malaysia, Brunei and Taiwan.

Indonesia has also confronted the Chinese coast guard and fishing fleets in the gas-rich Natuna Sea on the fringes of the South China Sea.

“Incidents in the waters tend to overshadow the importance of what lies beneath,” Philippine Foreign Assistant Secretary Marshall Louis Alferez said.

“The seabed and the subsoil extending from our archipelago up to the maximum extent allowed by UNCLOS hold significant potential resources that will benefit our nation and our people for generations to come.”

"Today, we secure our future by making a manifestation of our exclusive right to explore and exploit natural resources in our extended continental shelf entitlement,” Alferez said.

The 1982 UN convention

Under the 1982 UN convention, a coastal state could have exclusive rights to exploit resources in its continental shelf, a vast stretch of seabed that can extend up to 648 kilometres including the right to authorise and regulate any kind of drilling.

The Philippines’ undersea continental shelf could potentially overlap with those of other coastal states in the South China Sea, including that of Vietnam. Philippine officials expressed readiness to hold talks to resolve such issues based on UNCLOS.

Philippine Permanent Representative to the UN Antonio Lagdameo said the move “can reinvigorate efforts of states to demonstrate their readiness to pursue UNCLOS processes in the determination of maritime entitlements and promote a rules-based international order."

Hostilities and tensions in the disputed waters have alarmingly escalated particularly between China and the Philippines over two disputed shoals since last year.

Chinese Coast Guard ships and suspected militia vessels have used powerful water cannons and dangerous blocking maneuvers against Philippine Coast Guard patrol ships and navy boats that have injured Filipino navy personnel, damaged their supply boats and strained diplomatic relations between the two countries.