TOKYO—Japanese, U.S., Australian and Philippine defense ministers are planning to hold their first-ever quadrilateral talks in Singapore next month, a diplomatic source said Tuesday, amid China's growing maritime assertiveness in the Indo-Pacific region.
The ministerial gathering would be held as Japan, the United States and Australia have been each bolstering their defense cooperation with the Philippines, while trying to showcase their collaboration as a group of four nations surrounding the Pacific.
The meeting by the United States and its three security allies in the Pacific would take place on the sidelines of the annual Asia Security Conference, known as Shangri-La Dialogue, scheduled for three days through June 4 in the Southeast Asian city-state.
The four ministers are likely to explore how to strengthen their security cooperation, with concern mounting over Beijing's increasing military presence in the South and East China seas -- one of the sources of Sino-U.S. tensions.
Japanese Defense Minister Yasukazu Hamada, U.S. Secretary of Defense Lloyd Austin, and their Australian and Philippine counterparts, Richard Marles and Carlito Galvez, are set to participate in the quadrilateral gathering.
The ministers are also certain to exchange views on a joint maritime patrol by vessels of the four countries in the South China Sea, home to some of the world's busiest sea lanes, aimed at deterring illicit activities there, according to the source.
Such a joint patrol could play a crucial role in monitoring and limiting the movements of the Chinese military.
On Thursday, Japan, the United States and the Philippines are expected to start joint drills involving their coast guards near Manila Bay, while planning to set up a trilateral framework that includes their national security advisers.
Bilateral defense ties among the four nations have also been beefed up, with Tokyo providing patrol vessels to Manila and exporting an air radar system to the armed forces of the Philippines.
Japan and the Philippines, both facing challenges related to China's territorial claims in their nearby waters, have agreed to work toward signing a treaty designed to facilitate joint exercises and reciprocal visits between their forces.
In February, meanwhile, the Philippines granted the U.S. forces access to four military bases in the country. Later in the same month, Canberra and Manila discussed the possibility of carrying out joint patrols by their forces in the South China Sea.