The United States on Saturday reaffirmed its commitment to a defence treaty with the Philippines, which is currently embroiled in a territorial dispute with Beijing over the South China Sea, AFP reports.
The pledge came as US Defense Secretary Chuck Hagel met his Philippine counterpart Voltaire Gazmin on the sidelines of an annual security forum in Singapore set to be dominated by Beijing's growing might.
The Philippines, a former US colony, is involved not only in a row with China but also Taiwan over the recent killing of a Taiwanese fisherman along their sea border.
"Secretary Hagel emphasised the importance of the Philippines as a treaty ally and reaffirmed the United States commitment to the Mutual Defense Treaty," Pentagon spokesman George Little told journalists after the meeting.
"Secretary Hagel stressed the importance of maintaining freedom of navigation in the region," he added.
Both defence chiefs "also discussed deepening bilateral defense cooperation including work towards increasing rotational presence of US forces in (the) Philippines to address common challenges", Little said.
The Philippines and the United States, whose soldiers fought side by side in the Pacific theatre during World War II, are bound to help defend each other in case of external attacks under a mutual defence treaty signed in 1951.
The Philippines has one of Asia's most poorly equipped armed forces and has been protesting Chinese efforts to enforce Beijing's claims to the entire South China Sea, including waters and islands near the Philippine coast.
The Philippines along with Brunei, Malaysia and Vietnam as well as China and Taiwan have laid full or partial claim to the South China Sea, which is believed to sit atop vast deposits of natural gas and hosts vital shipping lanes.
Taiwan threatened the Philippines with sanctions and held naval exercises near their sea border after a Taiwanese fisherman was killed when the Filipino coastguard fired on their vessel on May 9.