MANILA (Reuters) - The Philippines plans to install a 50 million peso (S$1.5 million) satellite-based system to track commercial flights over the disputed South China Sea, after China landed its first test flights this month on a reef it built in the Spratly islands.
China's increasing military presence in the Spratlys has stirred fears it could lead to an air defence zone the country controls, which would escalate tension with other claimants, and the United States, in one of the world's most volatile areas.
China claims almost the entire South China Sea, believed to have huge oil and gas deposits, but Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims in the sea, through which about US$5 trillion in trade passes every year.
"In the absence of a radar in the area, the system will help track aircraft movements, enhancing safety and security," said Mr Rodante Joya, a deputy director-general of the Civil Aviation Authority of the Philippines.
Mr Joya said the Philippines would install the surveillance system on the island of Thitu, calling it by its Philippine name of Pagasa, to track about 200 commercial flights through the area each day.
The area in the South China Sea is among the blind spots in the Philippines' airspace, he added.
The Philippines and Vietnam protested against China's test flights on the Fiery Cross reef this month, saying Beijing might impose an air defence identification zone, restricting flights by commercial airlines over the South China Sea.
On Jan 7, China warned a small civilian plane carrying Philippine aviation officials who inspected Thitu, where the surveillance equipment is to be set up this year, as their craft flew near Beijing's man-made island.
"The Foreign Ministry has been informed about the reported incident involving our civil aviation team," presidential spokesman Herminio Coloma told reporters, adding that the foreign ministry was expected to make a statement on the matter.
The Philippine civil aviation agency has limited radar coverage and the military is expected to sign a deal this year for three aerial radars to detect airspace intrusions as far as 402km away, beyond the exclusive economic zone.
Mr Joya said the agency was waiting for approval from security and foreign affairs officials as the tracking system, or automatic dependent surveillance broadcast system, as it is called, is to be located on a military base in a disputed area.
Seven civil aviation radar stations will also be added, he said.