Japan, US, Philippines Conduct Joint Naval Exercises Amid South China Sea Tensions

Naval forces from Japan, the Philippines, and the United States carried out a coordinated maritime exercise in the South China Sea on September 13, signaling strengthened defense collaboration amidst rising regional tensions. The operation featured Japan Maritime Self-Defense Force’s JS Osumi (LST-4001), alongside vessels from the Philippine Navy and the U.S. Navy, participating in what officials termed a Multilateral Maritime Cooperative Activity (MCA).

These exercises took place in waters where China has increased naval and coast guard presence in recent months, triggering concerns among Southeast Asian countries and Western partners. In a joint declaration, the three nations reiterated their commitment to maintaining a “Free and Open Indo-Pacific,” a strategic initiative promoting adherence to international law, free commerce, and freedom of navigation.

The statement emphasized, "This activity underscores our shared dedication to regional stability and maritime security, in accordance with international law, including the United Nations Convention on the Law of the Sea (UNCLOS)."

The South China Sea continues to be a critical hotspot in diplomatic relations and U.S.-China interactions, largely due to China’s extensive territorial claims. These claims were ruled unlawful by an international tribunal in 2016. Recently, Chinese vessels have been reported to interfere with Philippine resupply missions to military outposts within its exclusive economic zone, prompting diplomatic protests and amplified calls for international support.

This joint maritime drill reflects an ongoing effort to enhance security cooperation between Washington, Tokyo, and Manila as they respond to China’s increasingly assertive maneuvers in the contested waters.

The South China Sea remains a strategic maritime corridor, with approximately $3 trillion in global trade navigating these routes annually, underscoring the importance of maintaining stability and lawful conduct in the region.