The United States plans to increase the number of military and humanitarian drills it conducts in the Asia-Pacific as part of a new strategy to counter China's rapid expansion in the East Vietnam Sea, the Philippine military said on Wednesday.

Admiral Harry Harris, commander of the U.S. Pacific Command, highlighted key aspects of the Pentagon's freshly drafted Asia Pacific Maritime Security Strategy during talks with his Filipino counterpart, General Hernando Iriberri, during a visit to Manila.

Colonel Restituto Padilla, a military spokesman, told journalists that the report outlined Washington's set of actions in the disputed East Vietnam Sea and East China Sea, focusing on the protection of "freedom of seas", deterring conflict and coercion, and promoting adherence to international law.

China claims most of the East Vietnam Sea, through which $5 trillion in ship-borne trade passes every year. The Philippines, Vietnam, Malaysia, Taiwan and Brunei also have overlapping claims.

A military source, who was in the meeting between Harris and Iriberri, told Reuters the U.S. and the Philippines are expected to increase the size, frequency and sophistication of exercises in the region.

Since China's land reclamation efforts began in December 2013, it has reclaimed more than 2,900 acres (1,170 hectares) of land as of June 2015, the Pentagon said last week in a report on its Asia-Pacific Maritime Security Strategy.

The reclamation campaign significantly outweighed efforts by other claimants in size, pace and nature, the Pentagon report said.

China says the outposts will have undefined military purposes, as well as help with maritime search and rescue, disaster relief and navigation.