Philippines says China wants to survey seas to its east

Congressman Gary Alejano shows to the media the supplemental impeachment complaint he filed against President Rodrigo Duterte Thursday, March 30, 2017 at the Lower House in suburban Quezon city northeast of Manila, Philippines. Alejano, who cited in his earlier March 16, 2017 complaint, the thousands of deaths that have happened in Duterte's anti-drug crackdown as well as his alleged corruption, filed a supplemental impeachment complaint Thursday allegedly "for failure to assert the Philippines' exclusive sovereign rights over the Benham Rise, and his refusal to raise the issue over the plan of China to construct an environmental monitoring station in the disputed Scarborough Shoal."(AP Photo/Bullit Marquez) (The Associated Press)

Congressman Gary Alejano talks to the media as he files a supplemental impeachment complaint against President Rodrigo Duterte Thursday, March 30, 2017 at the Lower House in suburban Quezon city northeast of Manila, Philippines. Alejano, who cited in his earlier March 16, 2017 complaint, the thousands of deaths that have happened in Duterte's anti-drug crackdown as well as his alleged corruption, filed a supplemental impeachment complaint Thursday allegedly "for failure to assert the Philippines' exclusive soverign rights over the Benham Rise, and his refusal to raise the issue over the plan of China to construct an environmental monitoring station in the disputed Scarborough Shoal."(AP Photo/Bullit Marquez) (The Associated Press)

Congressman Gary Alejano shows to the media the supplemental impeachment complaint he filed against President Rodrigo Duterte Thursday, March 30, 2017 at the Lower House in suburban Quezon city northeast of Manila, Philippines. Alejano, who cited in his earlier March 16, 2017 complaint, the thousands of deaths that have happened in Duterte's anti-drug crackdown as well as his alleged corruption, filed a supplemental impeachment complaint Thursday allegedly "for failure to assert the Philippines' exclusive sovereign rights over the Benham Rise, and his refusal to raise the issue over the plan of China to construct an environmental monitoring station in the disputed Scarborough Shoal."(AP Photo/Bullit Marquez) (The Associated Press)

The Philippines says China wants to survey potentially resource-rich seas off the country's northeast coast but Manila will agree only if a Filipino scientist is allowed to observe.

Acting Foreign Secretary Enrique Manalo told ABS-CBN News Channel on Thursday that a number of Chinese requests to survey Benham Rise have been denied because China rejected that condition. Some requests are still pending.

Defense Secretary Delfin Lorenzana has said that Chinese survey ships were spotted crisscrossing the Benham Rise area from July to December last year.

It was not clear what the ships were doing. The area is on the opposite side of the Philippines from where the countries are locked in a dispute over ownership of islands and shoals in the South China Seas.