The Philippines Department of Foreign Affairs filed a claim with the UN on Friday to formally recognize the boundaries of its underwater continental shelf in the South China Sea, granting it exclusive rights to utilize the area’s resources. The Philippines filed the claim with the UN Commission on the Limits of the Continental Shelf following more than 15 years of scientific research on the scope of its undersea shelf in the South China Sea, located off the western coast of Palawan province.

The resource-rich undersea area for which the Philippines is seeking formal recognition of its sovereign rights under the UN Convention on the Law of the Sea (UNCLOS) includes the Spratlys—a chain of islands, islets, reefs, and atolls that has been hotly contested by China, the Philippines, Vietnam, Malaysia, Brunei, and Taiwan. Friday’s filing acknowledged that under Article 76 of the UNCLOS, a coastal state may have exclusive rights to exploit resources on its continental shelf, which can extend up to 350 nautical miles (648 kilometers). This includes the authority to permit and regulate drilling activities.

In Friday’s press release issued by the Philippine Mission to the UN, Philippine Foreign Assistant Secretary Marshall Louis Alferez stated:

Incidents in the waters tend to overshadow the importance of what lies beneath … 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.”

The announcement comes just a day after the Armed Forces of the Philippines declared that maritime law enforcement agencies are prepared to protect Filipino fishermen from China’s “anti-trespassing policy[.]” Order No. 3, issued by the China Coast Guard, authorizes its personnel to detain trespassing foreign ships and crews for 30 to 60 days without trial within waters claimed by China. China has not yet responded to Friday’s filing.

This is the same disputed area that led the Philippines to take its conflicts with China to international arbitration in 2013. In 2016, the arbitration panel dismissed China’s claim to nearly all of the South China Sea. However, Beijing declined to participate in the arbitration, rejected the ruling, and continues to ignore it.

This is the second time the Philippines has filed a claim with the UN Commission on the Limits of the Continental Shelf. The first claim was in 2009 for the area formerly known as Benham Rise, now the Philippine Rise, which the Commission officially recognized on April 12, 2012. In that 2009 submission, the Philippines stated its intention to reserve the right to submit claims for additional areas in the future.