The Philippine Navy (PN) has deployed Naval Task Group 80.5 aboard BRP Antonio Luna (FF-151) for the second Association of Southeast Asian Nations–United States Maritime Exercise (AUMEX 2025) in Batam, Indonesia, an initiative viewed as part of a broader effort by Southeast Asian states and Washington to counter China’s growing presence in the region.

Commodore Peter Jempsun V. De Guzman, commander of the PN’s Naval Defense Command, said the Navy’s participation reinforces the country’s presence in joint maritime operations amid mounting security challenges in regional waters.

The contingent will train with ASEAN and US forces from Dec. 8 to 14. A send-off ceremony was held on Dec. 4 at Naval Operating Base Subic in Zambales.

De Guzman noted that this year’s theme, “Cooperative Readiness for Maritime Crisis Response,” highlights the need for coordinated action in handling complex maritime situations.

“This exercise aims to enhance multilateral information sharing, incident response, and interoperability in the maritime domain,” De Guzman said.

He added that the drills provide the PN an avenue to demonstrate its preparedness and operational competence while strengthening defense ties with ASEAN partners and the US.

The first iteration of AUMEX took place in the Gulf of Thailand in 2019 and involved naval forces from Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Singapore, Thailand, Vietnam, Philippines, and US.

Throughout that exercise, ASEAN and US forces operated under a combined task force structure and trained on realistic scenarios intended to improve interoperability in areas such as visit, board, search and seizure (VBSS), maritime domain awareness, division tactics, and maritime asset tracking.

Commercial vessels contracted by the US were used as simulated target ships, allowing multinational teams to conduct VBSS operations against a range of scenario-based maritime threats.

The latest exercise came as the US urged stronger regional cooperation to deter China’s expansionist claims in Southeast Asia.

Last month, US Defense Secretary Pete Hegseth called on ASEAN nations to remain resolute and strengthen their maritime capabilities in response to China’s increasingly “destabilizing” actions in the South China Sea.