BALABAC, Philippines, May 18 (Reuters) - When the Philippine military chief addressed a small contingent of navy officers on a remote island in Palawan province near the disputed Spratly archipelago in the South China Sea, he reminded them their mission was to "ensure there is peace".

But he also told them they have a "very important" role to play in guarding Philippine waters against intruders - and assured them of more resources and troops as the Philippines shifts its focus from internal security to territorial defence.

"We make sure that we are deployed where we are needed. In Palawan, we are needed here because this is a strategic location, so we have to be prepared," Centino said after sharing a feast with troops over a banana leaf-lined table bedecked with crabs, chicken, rice, fruits and slices of roasted pig.

Centino's visit at the Narciso del Rosario naval station, site of a new beaching ramp and staging area, was his second stop in the Balabac group of islands, where he also inspected a 300-hectare Philippine air base.

The Balabac air base, whose location Centino called "very strategic" was one of four new sites the United States was given access to in February under a 2014 defence pact, which came at a time of concern over China's conduct in the South China Sea and tension over self-ruled Taiwan.

The 2014 Enhanced Defense Cooperation Agreement (EDCA) allows for joint training, pre-positioning of equipment and the building of facilities such as runways, fuel storage and military housing, but not a permanent presence.

Some local government officials have expressed reservations over the expanded EDCA, but Billy Adriano, a resident of Balabac, said he welcomed it because "that will help in the security of the country".

Manila has started building a 3-km (1.9-mile) runway at the air base, which will also host humanitarian assistance and disaster relief facilities and barracks that Americans could use under the EDCA.

"This is surrounded by islands, and this is where foreign vessels from international waters will enter and pass through our SLOCs (sea lines of communications)," Centino said of the air base's location.