American Navy and Coast Guard ships sailed with Filipino forces for maritime drills in the Philippines.

Footage shows the combined fleet sailing in the waters of Palawan and Occidental Mindoro on May 20.

The Armed Forces of the Philippines (AFP) said the joint drill was held during the 6th Bilateral Maritime Cooperative Activity (MCA) with the United States Indo-Pacific Command.

The Philippine army said in a statement: 'Marking a milestone in maritime collaboration, this was the first time the U.S. Coast Guard and the Philippine Coast Guard jointly participated in an MCA, highlighting a growing whole-of-nation approach to maritime cooperation.

'The activity featured a series of exercises, including Communications Check Exercise (COMMEX), Search and Rescue Exercise (SAREX), Division Tactics and Officer of the Watch Maneuver (DIVTACS/OOW), Photo Exercise (PHOTOEX), and Finish Exercise (FINEX).'

The United States and the Philippines are treaty allies under the 1951 Mutual Defense Treaty, pledging mutual support in case of an armed attack in the Pacific.

The significance of the alliance has been underscored amid escalating territorial tensions between the Philippines and neighbouring China over parts of the South China Sea.