US and Philippine forces have conducted their first joint live-fire drill close to parts of the South China Sea where China has territorial claims.

It was part of the largest-ever exercise between the two countries, taking place this month and involving over 17,000 troops.

The two militaries responded to a simulated attack from the sea on Wednesday off the northern island of Luzon. They worked on fine-tuning their coordination and cooperation.

They used artillery and a HIMARS rocket system to fire on a decommissioned ship representing an enemy.

The drill took place about 200 kilometers from the Scarborough Shoal, a flashpoint between Manila and Beijing.

The exercise was observed by President Ferdinand Marcos Jr., who has been shifting to closer defense cooperation with the US since taking office last year, apparently with China in mind.

Marcos is set to visit Washington next week and meet with President Joe Biden.