China on Sunday warned anew the Philippines to immediately halt what it described as “provocative actions” that could further heighten tensions in the South China Sea (SCS).

This came after the Armed Forces of the Philippines (AFP) reported that it had conducted an 11th Multilateral Maritime Cooperative Activity (MMCA) with partners, the Japan Maritime Self-Defense Force (JMSDF) and the United States Indo-Pacific Command (USINDOPACOM), in the West Philippine Sea (WPS), from 12 to 13 September 2025. 

The recent exercise, held off Magalawa Island in Palauig to Silanguin Island in San Antonio, Zambales, marks the second MMCA conducted in September, following the successful 10th iteration earlier this month.

The AFP’s continuous engagement highlights the ongoing partnership among the three countries to promote a rules-based international order in the Indo-Pacific.

For the 11th MMCA, the AFP deployed the BRP Jose Rizal (FF150), an AW109 anti-submarine helicopter, a Philippine Air Force search and rescue aircraft, a C-208B Intelligence, Surveillance, and Reconnaissance (ISR) plane, and four FA-50 fighter jets. 

The United States utilized the USS John Finn (DDG-113), along with a P-8A Poseidon maritime patrol aircraft, and two MH-60R helicopters. While Japan participated with the JS Osumi (LST4001), showcasing its amphibious operational capabilities.

These maritime exercises included a wide range of activities such as Communications Check, Maritime Domain Awareness, Anti-Submarine Warfare drills, Cross-Deck Landing, Naval Surface Interdiction and Clearance, Search and Rescue operations, and tactical maneuvers, all aimed at enhancing interoperability and readiness.

In a statement on Sunday, Tian Junli, spokesperson for the Chinese People's Liberation Army (PLA) Southern Theater Command, said Chinese forces conducted “routine patrols” in the South China Sea during the Philippines' joint maritime drills with Japan and the United States.

“We solemnly warn the Philippine side to immediately stop provoking incidents and engaging in actions that heighten tensions in the South China Sea,” Tian said. 

Tian said the troops of the Southern Theater Command "remain on high alert to resolutely safeguard China's territorial sovereignty and national security, and to uphold peace and stability” in the SCS. 

“Any attempt to stir up trouble or disrupt order in the South China Sea is doomed to fail,” said the spokesperson. 

Beijing claims nearly the entire South China Sea, a crucial maritime corridor for over $3 trillion in annual trade, despite competing claims from the Philippines, Vietnam, Indonesia, Malaysia, and Brunei. 

The Philippine government has renamed parts of these waters as the West Philippine Sea, reinforcing its territorial assertions around the Luzon Sea and the Kalayaan Island Group.

In 2016, the Permanent Court of Arbitration in The Hague ruled in favor of the Philippines, invalidating China’s sweeping claims. 

However, China has consistently rejected the tribunal’s decision.

The continuing drills by the Philippines, Japan, and the US reflect a collective effort to safeguard freedom of navigation and uphold regional peace, even as Beijing maintains a firm stance against what it calls “provocations.”