Philippine and US army soldiers salute as their national anthems are played during the opening ceremony of US-Philippines Arm-to-Army exercise at Fort Magsaysay, in Nueva Ecija province, north of Manila on March 13, 2023. (PHOTO / AFP)

MANILA - The Philippines identified on Monday four more of its military bases that the United States will get access to, almost doubling the number included in a defense agreement that seeks to advance a decades-old alliance between them.

The expansion of the Enhanced Defense Cooperation Agreement (EDCA) underlines the Philippines' strategic importance to the United States.

The EDCA, signed in 2014 under then US president Barack Obama, allows US access to Philippine bases for joint training, pre-positioning of equipment and building of facilities such as runways, fuel storage and military housing, but it is not a permanent presence.

President Ferdinand Marcos Jr' office on Monday said the four locations should "boost the disaster response" and help humanitarian and relief operations, adding defending the east cost was also taken into consideration

Defense chief Carlito Galvez called the sites "very strategic" and stressed the Philippines had a responsibility to the international community.

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"That's a trade route... where more or less $3 trillion trade passes (annually)," he said.

"Our responsibility to collectively secure that is huge."

Conflict concerns

The decision of President Ferdinand Marcos Jr to expand the US access was made in February but the announcement of the sites was delayed by opposition from some local government leaders.

Marcos' office on Monday said the four locations should "boost the disaster response" and help humanitarian and relief operations, adding defending the east cost was also taken into consideration.

The United States has committed more than $80 million worth of infrastructure at the five existing sites - the Antonio Bautista Air Base in Palawan, Basa Air Base in Pampanga, Fort Magsaysay in Nueva Ecija, Benito Ebuen Air Base in Cebu and Lumbia Air Base in Mindanao.

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US forces were evicted from Subic and Clark, the last and largest of their permanent bases in the Philippines, in 1992, amid a nationalist backlash. Ties were rebuilt after 2000, with multiple joint exercises each year.