MANILA - Acting Chief Justice Antonio Carpio on Thursday said the Philippines can enforce its arbitration victory against China without the latter's participation by entering into sea boundary agreements with other Southeast Asian nations.

"The Philippines and Vietnam can enter into a sea boundary agreement of their overlapping extended continental shelves beyond the Spratlys," Carpio said in a forum on the second anniversary of the arbitral tribunal ruling.

"A similar sea boundary agreement can be entered into between the Philippines and Malaysia to delineate their adjoining exclusive economic zones between Borneo and Palawan."

In 2016, an international court ruled in favor of Manila, declaring China’s expansive nine-dash line claim to the sea invalid. Beijing has ignored the landmark ruling.

Caprio, who was part of the Philippine legal team that made the case in The Hague, added that the Philippines can also file with the United Nations Commission on the Limits of the Continental Shelf an extended continental shelf claim off the coast of Luzon facing the South China Sea.

Carpio, meanwhile, urged the Department of Foreign Affairs (DFA) to ask the United States and the Philippines' Southeast Asian neighbors to make the Scarborough Shoal "an official red line" in the disputed sea.

"The DFA should campaign among ASEAN states, in particular among those states prejudiced by the nine-dashed line, to make Scarborough Shoal also ASEAN’s red line: that China cannot build on Scarborough Shoal," he said.

"The DFA should also campaign for the United States to make Scarborough Shoal the official red line under the Philippine-U.S. Mutual Defense Treaty. After all, it was President Obama who originally told President Xi Jinping in 2015 that Scarborough Shoal was a red line."

Indonesia, Malaysia, Taiwan, Brunei, Vietnam and the Philippines have overlapping claims in the sea. China maintains it owns most of the waterway and has been aggressively building and militarizing artificial islands.

Foreign Affairs Secretary Alan Peter Cayetano earlier said Manila had filed "several dozens" of protests against China, "maybe 50, 100."

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