The United States, the Philippines and Japan have begun joint naval exercises in the South China Sea, stepping up military coordination in one of Asia’s most contested waterways. The drills started early Saturday and include missile firing and anti-submarine warfare training.

The exercise comes as regional tensions remain elevated over disputed waters that China claims almost in full. The three-country operation signals continued security cooperation among allies and partners seeking to deter coercion and preserve freedom of navigation in the area.

The South China Sea has long been a flashpoint for overlapping territorial claims, with repeated encounters between Chinese vessels and ships from other countries. Military drills in the region are closely watched because they can affect both deterrence and the risk of miscalculation.

While the exercise is framed by officials as routine coordination, it underscores the wider strategic rivalry playing out across the Indo-Pacific. For neighboring states, the central issue remains how to maintain stability without conceding control of international waters to any one power.