Under a plume of black smoke, three cars parked on scrubland were crushed by missiles fired from about 600 metres (0.37 miles) away by three soldiers at a military base in the north of the Philippines.

The annual Balikatan manoeuvres follow a three-day Chinese military exercise that simulated targeted strikes and a blockade of self-ruled, democratic Taiwan, which Beijing considers part of its territory.

"As you're recently witnessing, there are some irresponsible behaviours that are ongoing and we should call those irresponsible behaviours out," US Army Pacific Commander General Charles Flynn told reporters at the site, without elaborating further.

Flynn added that the war games were an important show of "collective commitment to maintain a free and open Indo-Pacific".

Philippine Army chief Lieutenant-General Romeo Brawner praised the "effectivity" of Javelins against Russian tank and armour in the Ukraine war, adding Manila plans to acquire the weapon in the future.

"We want to also bring that capability to the Philippine Army in order for us to be able to bolster our defensive posture and be able to defend our territory," Brawner added.

The two allies also plan to hold new exercises in the South China Sea later in the year that will include other countries, US Defence Secretary Lloyd Austin announced in Washington on Tuesday, after a meeting with the Philippine defence and foreign secretaries and US Secretary of State Antony Blinken.

The exercise aims to boost Manila's military capability while serving as a US show of support for its Asian ally amid China's growing assertiveness.

Nearly 18,000 troops are taking part in the annual exercises, which for the first time will include the sinking by live fire of a decommissioned Philippine navy warship in the South China Sea, waters that Beijing claims almost entirely.

It follows a deal announced last week for US forces to use an increased number of bases in the Philippines, including one near Taiwan.

The exercises and growing US access to Philippine bases have angered China.

"Facts speak louder than words. Judging from the locations of the new military bases, the intention behind those sites is more than obvious," Chinese foreign ministry spokesman Wang Wenbin told reporters in Beijing on Wednesday.

He warned: "We would like to once again remind the relevant country in the region that pandering to forces outside the region will not bring greater security, but will cause tensions, put regional peace and stability at risk, and eventually backfire."

Balikatan will include military helicopters landing on a Philippine island off the northern tip of the main island of Luzon, nearly 300 kilometres (180 miles) from Taiwan, and the retaking of another island by amphibious forces.

It will be the first time the exercises have been held under President Ferdinand Marcos, who plans to watch the ship sinking on April 26.

He has sought to strengthen ties with the United States after his predecessor Rodrigo Duterte weakened the alliance.