The 10-year agreement, signed in 2014 but not implemented due to legal challenges, will see more US troops and warships rotate through the Philippines, and the hosts will receive help in building military facilities.

Supreme Court spokesman Theodore Te said the accord was upheld with a 10-4 vote, ruling that President Benigno Aquino’s government had the authority to sign the pact and did not need congressional approval.

The pact “is a mere implementation of existing laws and treaties,” Te said.

Aquino negotiated the accord to help the Philippines improve its military capabilities and draw the United States closer, partly to counter a fast-expanding Chinese presence in disputed parts of the South China Sea.

US President Barack Obama also pushed hard for the Enhanced Defense Co-operation Agreement (EDCA) as part of his so-called strategic “pivot” to Asia that has involved strengthening the American military presence in the region.

However it faced immediate legal challenges from groups opposed to US military involvement in the Philippines, a US colony from 1898 to 1946.

The Philippines hosted two of the largest overseas US military bases until 1992, the year after the Philippine Senate voted to end the leases in the face of strong anti-US sentiment.

Philippine military chief General Hernando Iriberri immediately welcomed Tuesday’s ruling, saying the accord would help the country address short-term “capability gaps” and modernize its armed forces.

Iriberri also emphasized the pact would help the Philippines “maintain maritime security,” a term commonly used when referring to efforts to contain China’s expansion in the sea.

The US embassy in Manila also hailed the decision.

“EDCA is a mutually beneficial agreement that will enhance our ability to provide rapid humanitarian assistance and help build capacity for the Armed Forces of the Philippines,” a statement said, AFP reported.

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