MANILA - Pristine corals, diverse marine life and untapped gas reserves. These, according to marine scientists, are the treasures at stake in Benham Rise, an undersea plateau off the Philippines' Pacific coast that has become a new flashpoint between the Philippines and China.

Marine scientists from the Bureau of Fisheries and Aquatic Resources, University of the Philippines, and Oceana Philippines had documented a "vast and pristine" coral reef ecosystem during an expedition in Benham in May 23 to 31 last year.

"We saw terraces of corals, as far as the eye could see. It's so exciting to know that we have such a vast and pristine coral reef ecosystem within Philippine territory," Marianne Pan-Saniano, marine scientist for Oceana Philippines, said in a newsletter.

At Benham Bank, the shallowest area of Benham Rise, the expedition team found "a dazzling array of soft and hard corals, fish, algae, and sponges," the non-profit group said.

Several sites in the bank boast of "one hundred percent coral cover," Oceana said.

The group added that Benham Bank was also home to the bluefin tuna and other in-demand fish species, making it a commercial source of food.

“This could serve as a new alternative fishing grounds for Filipino fishermen, since the area is known as the migration path of
fish," BFAR chief scientist Rhoda Bacordo was quoted as saying by Oceana.

Oceana confirmed that there were also potential oil and natural gas reserves elsewhere in Benham Rise, but it cautioned that exploration should be tempered with conservation efforts to minimize threats to the region’s biodiversity.

Chinese foreign ministry spokesperson Geng Shuang confirmed Monday that Chinese vessels recently passed through Benham Rise for "marine research," but insisted this was only in exercise of the principle of "freedom of navigation" and "right to innocent passage."

Defense Secretary Delfin Lorenzana said Chinese ships had no business in those waters and that their prolonged stay was not merely an " innocent passage."

President Rodrigo Duterte however said Thursday that he was "advised way ahead" before Beijing sent ships to the region.

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Benham Rise is the latest addition to Philippine territory. It was awarded to the country in 2012 by the United Nations after Manila successfully proved that it is part of Isabela province's extended continental shelf. -- With Reuters