Personnel from Japan, the United States, the Philippines and Australia have held their first joint maritime exercise in the South China Sea.
The Philippine military says what it calls the "first Multilateral Maritime Cooperative Activity" took place in waters in the country's exclusive economic zone on Sunday.
It says the activity involved vessels and aircraft, including Philippine ships and the Japan Maritime Self-Defense Force destroyer Akebono, as well as a US littoral combat ship and an Australian frigate.
The Philippine military also says they conducted communication training and other drills that "were designed to enhance the different forces' abilities to work together effectively in maritime scenarios."
The defense chiefs of the four countries issued a joint statement ahead of the exercise. It said the four nations "uphold the right to freedom of navigation and overflight, and respect for maritime rights under international law, reflected in the UN Convention on the Law of the Sea."
Last month, on two occasions, China Coast Guard members fired water cannons at a Philippine resupply ship in disputed waters in the South China Sea. The Philippine government said some of the sailors were injured in each of the incidents.
Analysts say the joint exercise was intended to deter Chinese actions in the waters.