THE PHILIPPINES has protested Chinese incursions in the South China Sea more than 60 times since President Rodrigo R. Duterte became president in 2016, his top diplomat told lawmakers yesterday.

Of the 63 diplomatic notes, Manila had issued 29 notes verbale — a less formal note that is drafted in the third person and never signed — based on intelligence information provided by its military, Foreign Affairs Secretary Teodoro L. Locsin Jr. said at a House of Representatives hearing discussing his agency’s 2020 budget.

“We have filed diplomatic protests at every turn,” he told congressmen. “When they tell me that there is a violation of our rights, I file diplomatic protests,” he said of the Philippine Army.

“I have changed the language of our diplomatic protest from the usual niceties to direct protests, no nice words anymore,” he added.

In 2016, the United Nations Permanent Court of Arbitration in the Hague voided China’s claim to more than 80% of the South China Sea. China has rejected the ruling.

Mr. Duterte raised the nation’s arbitral win during his meeting with Chinese President Xi Jinping last week as he faces mounting domestic pressure to take a tougher stance after a collision that sank a Filipino fishing boat at Reed Bank in June.

The president told Mr. Xi that the 2016 United Nations ruling was “final, binding and not subject to appeal.”

His Chinese counterpart was unmoved, saying there won’t be any change to Beijing’s position on the sea dispute, according to presidential spokesman Salvador S. Panelo.

During the meeting, both parties agreed to form a steering committee for joint exploration in the South China Sea.

Mr. Locsin said the Chinese government had answered Mr. Duterte’s call for foreign vessels to seek permission from Philippine authorities before sailing in its territorial waters.

“When warships were seen in the West Philippine Sea, the President said he will not allow that,” he said, referring to parts of the South China Sea within the Philippines’ exclusive economic zone. “And he said he will demand permission. To our surprise, China’s answer was, ‘That’s exactly what we want. We want to ask permission.’”

Five Chinese warships passed through the Sibutu Strait in southern Philippines in July and August without notifying local authorities, the military has said.

Last month, Mr. Duterte said foreign ships that enter Philippine waters would face “unfriendly” treatment if they failed to notify authorities.

Mr. Locsin said Western vessels had not sought permission to sail in Philippine waters. “The problem is western naval powers do not, as a matter of principle, never ask for permission, because they insist on total and absolute freedom of navigation,” he said.

The Foreign Affairs chief called a “total fabrication” a report that Mr. Duterte had been apologetic when he raised the Philippines’ arbitral win.

“The president has, in my experience in his visits to China, always raised the arbitral award,” he said. Mr. Locsin then sought a closed-door meeting with congressmen to discuss details of what the president told Mr. Xi. — Vince Angelo C. Ferreras