After Phillipines's key ministers rebuked Beijing over the presence of Chinese vessels in the contested waterway, President Rodrigo Duterte said on Tuesday that he has barred his ministers from talking about South China Sea in public.

China's maritime conduct has been a constant problem for Duterte but he has refrained from criticising Beijing and instead praised its leadership, hoping to secure investment, according to Reuters.

But after weeks of rebukes of China by his ministers over the presence of hundreds of fishing vessels in the Philippines' Exclusive Economic Zone (EEZ), he told his ministers on Monday they must refrain from discussing the matter.

Philippine President Rodrigo Duterte gestures during his fourth State of the Nation address at the Philippine Congress in Quezon City, Metro Manila, Philippines, July 22, 2019. REUTERS/Eloisa Lopez

"If we talk, we talk but just among us," he said in a televised address.

On Tuesday, he said his order should not be construed as weakness and that maritime patrols must continue.

"Our agencies have been directed to do what they must and should to protect and defend our nation's interest," Duterte said in a statement. "We will not waver in our position."

Beijing claims almost the entire South China Sea and has built military installations equipped with missiles on reefs in disputed areas, including within the Philippine EEZ, alongside a constant presence of coastguard and fishing vessels.

While China’s conduct has been a constant problem for Duterte, the Philippine president has refrained from criticising Beijing and instead praised its leadership, hoping to secure big investments, Al Jazeera reported.

But his approach has frustrated nationalists.

Earlier in May, Duterte’s Foreign Affairs Secretary Teodoro Locsin Jr took to Twitter to demand China leave the waterway.

The foreign secretary’s online swearing prompted a rebuke from Beijing and he later apologised to his Chinese counterpart.

Chinese vessels, believed to be manned by Chinese maritime militia personnel, are seen in the Philippines’ EEZ on March 27, 2021 [File: Philippine Coast Guard/National Task Force-West Philippine Sea/Handout via Reuters]

Presidential spokesman Harry Roque told reporters on Tuesday that Locsin was still allowed to address the issue in public, since it was part of his portfolio.

“The instruction of the president was clear. Only the secretary of foreign affairs and myself can speak on the issue now,” Roque said during a press briefing.

The gag order could lessen tensions at the rhetorical level, said Aaron Jed Rabena of the Asia-Pacific Pathways to Progress, a Manila-based think tank.

"It could be that President Duterte has realised that it's high time for his administration to speak with one voice given the mixed signals...which show a government that is incoherent," Rabena said.

Philippines tells fishermen to ignore Beijing's ban on fishing in South China Sea

Tensions between the Philippines and China have escalated since March.PHOTO: EPA-EFE

The same day Duterte announced the gag order, the foreign ministry filed another diplomatic protest against China over the annual summer fishing ban Beijing imposed in the South China Sea from May 1 to August 16, saying it was "a violation of Philippines' sovereignty and sovereign rights".

"This fishing ban does not apply to our fishermen," the Philippines' South China Sea taskforce said in a statement.

The taskforce opposed China's imposition of the ban over the areas within the territory and jurisdiction of the Philippines, adding "our fisherfolk are encouraged to go out and fish in our waters in the WPS (West Philippine Sea)"

The Chinese embassy in Manila did not immediately respond to a request for comment.

Manila, which refers to area as the West Philippine Sea, has for years been embroiled in a dispute over Beijing's sweeping claims of sovereignty over the South China Sea.

An international tribunal in 2016 invalidated China's claims, but China has rejected the ruling.

Tensions between the two countries have recently escalated after Manila accused China of territorial incursions by hundreds of its vessels in the resource-rich waterway.

The Philippines has filed diplomatic protests against China over what it calls the "illegal" presence of the Chinese vessels, which it says are manned by militia.

Chinese diplomats have said the boats were just sheltering from rough seas and no militia were aboard.

The Philippines' South China Sea taskforce said it spotted seven "Chinese Maritime Militia" at the Sabina shoal in the disputed Spratly archipelago on April 27, which dispersed after being challenged by the Philippine coast guard.

Five returned two days later but left after the Philippine coast guard arrived, it said. Sabina shoal is around 130 nautical miles from the western Philippine island of Palawan.

"The Philippines is not deterred from defending our national interest, patrimony, and our dignity as a people with all that we have," the task force said.

Chau Polly