Quadrilateral Maritime Exercise in the South China Sea
On April 7, 2023, Japan, the United States, the Philippines, and Australia conducted a joint maritime exercise in the South China Sea. This exercise, involving the Japanese Maritime Self-Defense Force destroyer Akebono, the US Navy's littoral combat ship Mobile, and Australian and Philippine frigates, was the first multilateral maritime cooperative activity for the group.
The exercise, held in the Philippine exclusive economic zone (EEZ), included communication drills, a passage near the Ayungin Shoal, and planned anti-submarine warfare training. The Ayungin Shoal has been a site of tension, with Chinese vessels accused of harassing Filipino ships.
In a joint statement, the four countries affirmed their commitment to freedom of navigation and overflight, and respect for maritime rights under international law. This statement is seen as a response to China's land reclamation and militarization activities in the Spratly Islands.
The exercise was completed as planned on April 8, 2023. Philippine President Ferdinand Marcos Jr. expressed hope that the exercise would deter conflict with China.
On the same day, China's military conducted a joint air and sea patrol in the South China Sea, stating their awareness of all military activities disrupting regional stability and creating conflict.
The Philippines, with limited naval resources, sees defense cooperation with the United States and its allies as crucial to countering China's growing assertiveness in the South China Sea. The first-ever Japan-US-Philippines trilateral summit is scheduled to be held in Washington on April 11, 2023.