MANILA — A senator and ally of President Rodrigo Duterte is asking him to rethink his “hands-off” approach in dealing with the South China Sea.

Duterte has drawn criticism for his response to the alleged Chinese encroachment on Benham Rise and reports that Beijing is also planning to build a station in Scarborough Shoal.

Reacting to reports that China plans to build a monitoring station in Scarborough, Duterte recently said that the Philippines cannot do anything to stop China from altering the disputed shoal, located some 124 nautical miles from Zambales.

China has since denied the report.

Senator Sherwin Gatchalian said Duterte’s approach on the issue is wrong and the president must stand up to China.

"It is incorrect to say that there is nothing we can do to stop China. We still have several legal and diplomatic options, all of which must be exhausted in defending Philippine territory from foreign aggression,” Gatchalian said.

“The Philippines should never allow itself to be bullied by anyone, no matter how big and powerful that bully might be.”

Gatchalian said Duterte must also invoke the Philippines' legal victory against China should Beijing step up its aggression in the South China Sea.

Last July, a United Nations-backed arbitral tribunal invalidated China’s so-called nine-dash line claim to the South China Sea. It also said, Scarborough Shoal is a traditional fishing ground of the countries surrounding it and China may be violating the Philippines' sovereign rights by blocking access to it.

"The favorable decision in the Philippines vs. China case is a potent tool we can use to enforce our sovereign rights in the West Philippine Sea. It is our duty to invoke this ruling and take action before international legal institutions to contest any further acts of Chinese aggression in the West Philippine Sea," Gatchalian said.