MANILA - Several lawmakers on Wednesday raised concerns over a China-controlled company's 40-percent stake in the Philippines' lone power transmission line, saying this could compromise national security.

State Grid Corp. of China, which owns a 40-percent stake in the National Grid Corporation of the Philippines (NGCP), can turn off the Philippines' power transmission grid "remotely," Senate President Pro-Tempore Ralph Recto said during budget deliberations.

"Part of the plan of China Telecom is to use the wires of NGCP for their mid-mile telecommunication," Recto said, referring to the Chinese firm that is part of the consortium to operate the country's third telco.

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"They can turn it off remotely. Ang giyera naman na darating ganon na (War starts that way), not necessarily missiles. Cyberwar," he said.

Although the law allows State Grid to own a 40-percent stake in NGCP, its concession agreement limits the firm from assigning Chinese officials to man the equipment, Senate Energy Committee chair Sherwin Gatchalian said.

"Regardless of the country, we have to make sure that safeguards are being implemented with regards to the transmission line kasi isa lang ang transmission line natin so natural monopoly 'yan (because we only have one transmission line so that's a natural monopoly)," Gatchalian told ABS-CBN News.

"The Chinese can give technical assistance... [but] only Filipinos can manage the transmission lines," he said.

While the law provides safety nets, it will not hurt to err on the side of caution, Gatchalian said.

"We should always be vigilant when it comes to the transmission line," he said.

"It's delivering power from Luzon all the way down to Mindanao. If someone will jeopardize our economy, they will just have to switch it off."

Sen. Panfilo Lacson, who defended the Department of National Defense's 2020 budget before lawmakers, said security officials have been closely monitoring China's stake in the country's vital infrastructure, including power and telecommunications.

The NGCP earlier allayed fears that its technical partner would try to shut down the Philippines' power lines.

"At the end of the day, it’s a business,” NGCP spokesperson Cynthia Alabanza said.

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