MANILA (UPDATE) - The Philippine Navy chief on Saturday inspected two retired gas platforms being considered for conversion into military observation posts for Recto Bank and the Malampaya gas field in the West Philippine Sea.

The visit of Flag Officer In Command Navy Vice Admiral Giovanni Bacordo to Nido and Matinloc gas platforms came as China again rejected the 2016 arbitral ruling that invalidated its sweeping claims over the South China Sea.

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The two gas platforms' location northwest of Palawan is considered to be "strategic and vital" due to its proximity to Recto Bank, Malampaya and Galoc Gas Fields, the Philippine Navy said in a statement.

Malampaya Gas Field, located 80 kilometers off Palawan's coast, began commercial operations in 2001 and supplies natural gas to 5 power plants in Luzon, which together generate over 3,200 megawatts of power.

The Nido and Matinloc gas platforms ceased operations last year after 40 years, the Navy said.

The energy department has offered the transfer of their ownership, and "it is the position" of the Department of National Defense"to acquire" and "expeditiously transfer" them to the Armed Forces of the Philippines.

The two platforms are being planned for conversion into Philippine Navy Littoral Monitoring Stations (LMS).

"This inspection intends to look at the viability of these retired gas platforms to be converted to observation posts for Recto Bank and Malampaya gas platform," Bacordo said.

"This will further enhance our capability to protect our maritime interests in these strategic locations," he added.

The Navy said the new monitoring stations were a "welcome addition" in improving its capabilities to "better serve our maritime nation especially in its critical location near the nation’s source of natural gas."

In his participation Friday in a virtual meeting with 13 other Navy chiefs that included those of the United States and Australia, Bacordo echoed President Rodrigo Duterte's statement at the 75th United Nations General Assembly pertaining to the 2016 arbitral award.

Duterte had declared that the ruling was "now part of international law, beyond compromise and beyond the reach of passing governments to dilute, diminish or abandon."

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"We firmly reject attempts to undermine it," Duterte said of the award, without naming China, which ignored the arbitration proceedings in The Hague and continues to disregard the tribunal's ruling.

On the invitation of Adm. John Aquino, the US Pacific Fleet Commander, navy chiefs of Bangladesh, India, Japan, South Korea, Fiji, France, New Zealand, Tonga, Brunei, Malaysia and Singapore also took part in the virtual engagement, according to the Philippine Navy.

In August, Bacordo called for the filing of diplomatic protests against Beijing after two Chinese vessels were spotted surveying Recto Bank.

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Last year, a Chinese vessel left 22 Filipino fishermen adrift after sinking their boat near Recto Bank, leaving them to be rescued by Vietnamese fishers.

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Vietnam, Brunei, Malaysia, and Taiwan also have competing claims in the South China Sea, an important commercial waterway that is rich not only of marine resources but also potentially of gas and minerals.