The national government on Monday, Aug. 17, raised concern over China’s growing strategic position in the South China Sea, saying control of key features could give Beijing a commanding position over one of the world’s busiest maritime routes.

Philippine Coast Guard (PCG) spokesperson for the West Philippine Sea (WPS) Rear Adm. Jay Tarriela said Bajo de Masinloc, also known as Scarborough Shoal or Panatag Shoal, is the last remaining point needed to complete China’s “iron triangle” in the disputed waters.

“The strategic triangle or iron triangle of the People’s Republic of China is very concerning. I highlighted that Bajo de Masinloc is the last remaining part of that triangle,” Tarriela said during the National Maritime Council’s (NMC) first semester press briefing in Manila.

China has already established control over the Paracel Islands and built military facilities on several reefs in the Spratly Islands, according to Tarriela.

“Try to imagine if you’re going to connect the Paracel to Bajo de Masinloc, Bajo de Masinloc to the Spratlys, it will allow China to dominate the entire maritime space of the South China Sea,” he said.

Tarriela’s warning was revealed as NMC spokesperson Undersecretary Alexander Lopez reported that the government sustained patrols across the country’s maritime domain during the first half of the year.

From January to June, government agencies conducted 4,893 surface, logged 105,312 steaming hours, and covered 536,990 nautical miles. They also conducted 711 air patrols with 1,980 flying hours.

The PCG and Bureau of Fisheries and Aquatic Resources also carried out 4,433 maritime law enforcement operations involving violations of Republic Act No. 10654, the amended Fisheries Code, illegal, unreported and unregulated fishing, municipal fishery ordinances and other maritime laws.

But it is Scarborough Shoal’s strategic location that has become the focus of the NMC’s concern.

“This is disturbing because for China, they claim indisputable sovereignty in the entire water of the South China Sea,” Tarriela said.

Tarriela had made a similar warning in a Facebook post on Aug. 14, describing Bajo de Masinloc as “the last unfinished vertex” of China’s iron triangle.

In a social media post, Tarriela said the Paracels were seized by China in 1974 while seven reefs in the Spratly Islands have been dredged into military-armed island fortresses. Only Scarborough remains, he noted.

“If China militarizes it, the triangle closes and the danger stops being a Philippine problem,” Tarriela said.

He cited figures that showed the importance of the South China Sea to global commerce, saying about one-third of global shipping passes through the waterway while nearly $6.4 trillion worth of goods transited its straits in 2024.

He also said 40 percent of the world’s traded petroleum products and one-third of its liquefied natural gas pass through the area.

Tarriela said China’s actions in the South China Sea followed a pattern that could eventually be applied to Scarborough Shoal.

“First, they contest the patrols. Then they regulate the passage. The ‘nature reserve’ and unilateral baselines are the legal groundwork, coercion dressed as conservation,” he said.

“The playbook is proven: seize, normalize, legalize, enforce. It finished the Paracels. It finished the Spratlys. Bajo de Masinloc is in the final stage,” he added.

Meanwhile, the Armed Forces of the Philippines (AFP) revealed it has also detected changes in the composition of Chinese maritime forces operating in Philippine waters during the first six months of 2026.

AFP spokesperson for WPS retired admiral Roy Vincent Trinidad said the number of Chinese maritime militia vessels and PLA Navy ships decreased during the first semester of 2026 compared with the same period last year.

However, the number of Chinese coast guard vessels and PLA research vessels increased during the same period.

“There has been a decrease in the number of maritime militias, vessels, and PLA Navy ships in the first semester of 2025 vis-à-vis the first semester of 2026,” Trinidad said.

“The increase has been in the number of coast guard vessels and research vessels in the northern waters,” he added.

The admiral said the military has been monitoring the new emerging pattern in the country’s maritime domain through its land-based sensors.