The Philippine frigate BRP Jose Rizal, the Australian destroyer HMAS Brisbane and the Canadian frigate HMCS Ville de Quebec were participating in the operation, which a Philippine military official said was not directed at any country.

“Our activity is based on the premise that the exercise is anchored on the free and open Indo-Pacific with peace and prosperity in the region,” colonel Dennis Fernandez told a media briefing, adding that the joint sail was taking place within the Philippines’ exclusive economic zone.

The activity, which began on Sunday off the western province of Oriental Mindoro and will end in Palawan, is part of the ongoing military drills between the Philippines and Australia.

Called ALON, a Filipino word for ‘wave’, the 15-day joint exercises, which began on Aug 15, include amphibious and land operations as well as live fire exercises designed to enhance the abilities of the two militaries to cooperate better.

This year’s iteration is the largest joint activity to date, with 3,600 troops from both sides joined by a Canadian navy contingent as well as US marines.

ALON started in 2023, the same year Australia and the Philippines elevated their ties to a strategic partnership in order to address the rising security challenges in the region, including in the South China Sea, where US$3 trillion of annual shipborne commerce takes place.

Manila aims to increase the frequency of joint sails with foreign partners, Philippine navy spokesman rear admiral Roy Vincent Trinidad told reporters, saying that such activities help deter China’s aggression in the South China Sea.

Since late 2023, the Philippines has conducted “maritime cooperative activities” with allies, including joint passages with treaty ally the US.

Earlier this month, the Philippines and India also sailed together for the first time in the South China Sea.