The China Coast Guard boarded, inspected and drove away Philippine vessels that illegally intruded into waters near Ren'ai Reef in the South China Sea on Monday, a spokesman said on Monday afternoon.

Spokesman Gan Yu said the Philippines had violated its commitments by dispatching a supply ship and two inflatable boats into waters near Ren'ai Reef in the Nansha Islands, attempting to deliver supplies to a Philippine warship which has been grounded there for 24 years.

During the process, the Philippine supply ship "dangerously approached and deliberately collided" with a normally navigating Chinese vessel, he said.

The China Coast Guard took control measures in accordance with the law, including issuing warnings, boarding Philippine vessels and conducting inspections, and forcibly driving them away, Gan said, emphasizing that the actions were "reasonable, lawful, professional and standardized".

"We once again sternly warn the Philippine side: any form of infringement or provocation is futile," Gan said.

It was the first time the China Coast Guard has conducted onboard inspections of Philippine vessels.

An administrative law enforcement regulation for coast guard authorities that came into effect on Saturday said that China's actions in boarding, inspecting, intercepting and pursuing foreign ships must comply with relevant provisions of international treaties that China has acceded to.

The regulation also stipulates that foreign vessels illegally entering China's territorial waters or inland waters could be detained with the approval of the head of a city-level or higher coast guard authority.

Foreign Ministry spokesman Lin Jian told a regular news conference on Monday that the implementation of the regulation aims to enforce China's Coast Guard Law, standardize the administrative law enforcement procedures of coast guard authorities and better maintain maritime order, which aligns with international practices.

"On the South China Sea issue, China insists on resolving disputes through negotiations and consultations with directly concerned parties, while resolutely responding to any maritime infringement and provocative acts," he said.

Zhang Junshe, a former researcher at the Naval Research Academy, said the China Coast Guard's control measures against Philippine vessels were a justified and professional countermeasure, in line with international law, in response to the Philippines' escalating infringements and provocations in the South China Sea.

He added that this also serves as a deterrent to the Philippine side, which has frequently violated its commitments in the region.