Metro Manila, Philippines — Beijing has warned it will not sit idly by should Manila push through with its plan to build a permanent civilian structure on Ayungin Shoal, a disputed feature in the West Philippine Sea (WPS) which has seen heightened tensions between both sides this year.

Chinese Foreign Ministry Spokesperson Mao Ning told the press on Friday that such a “major move” by the Philippines would “severely infringe” on China’s sovereignty and would prompt the latter to take resolute measures.

“Ren’ai Jiao is an uninhabited shoal,” Mao said, referring to the name China uses for Ayungin. “According to the Declaration on the Conduct of Parties in the South China Sea signed by China and ASEAN countries, parties should keep Ren’ai Jiao uninhabited and facility-free.

The official was citing a non-binding declaration signed in 2002, which the two nations have previously accused each other of breaching.

“China will take resolute measures against any violation of our sovereignty and provocation, and firmly safeguard our territorial sovereignty and maritime rights and interests,” the spokesperson said.

Ayungin Shoal is located 104 nautical miles west of Palawan – well within the Philippines’ 200 nautical mile exclusive economic zone (EEZ).

Beijing, however, insists its sovereignty over the area, as it refuses to recognize the 2016 landmark arbitral ruling which invalidated its sweeping claims in the South China Sea.

Manila’s plan to put up a permanent structure there comes in the wake of continued Chinese harassment of Filipino vessels and fisherfolk this year.

These included the Asian giant’s dangerous use of water cannons and a military-grade laser, which not only triggered numerous diplomatic protests from the Philippines but also global condemnation.

The Philippine Navy ship BRP Sierra Madre is currently grounded at Ayungin to serve as the country’s military outpost in the WPS.

The Department of Foreign Affairs (DFA) earlier said the grounding was a deliberate move in response to China’s illegal occupation of Panganiban Reef, also known as Mischief Reef, in Manila’s EEZ. In 1995, Beijing constructed what it claimed was a “fisherman’s shelter” in the waters, but which the DFA said is now a militarized artificial island.