The Philippine Coast Guard said the country's recent rotation and resupply mission confirmed the active participation of "Chinese maritime militia vessels" in blocking the Philippine ships en route to the BRP Sierra Madre in Ayungin Shoal.
PCG spokesperson for the West Philippine Sea, Commodore Jay Tarriela, said the CCM's participation in intimidating Filipino troops was notably "covert" during the previous RoRe mission.
"But for this particular resupply mission, it has been very clear that the Chinese Maritime Militia are performing an active role to block the resupply mission," he said.
Tarriela identified the four CMM vessels as Qiong Sansha Yu 00231, 00115, 00114, and 00008, accompanying four other Chinese Coast Guard ships that conducted "dangerous maneuvers" against the Philippine Navy supply boats and the PCG ships.
The RoRe mission was successfully completed despite China's blocking and intimidation.
Meanwhile, National Security Council Assistant Director General Jonathan Malaya labeled these militias as part of the so-called "China's gray zone tactics"— a term often used by security experts to describe activities that are below the threshold of what constitutes aggression to prevent the country from using self-defense.
The Armed Forces of the Philippines earlier reported that more than 400 foreign fishing vessels are being monitored in the country's exclusive economic zone within the WPS.
Under the United Nations Convention on the Law of the Sea, foreign countries are allowed to conduct freedom of navigation and overflight operations within the EEZ.
However, only the Philippines has the exclusive right to exploit all natural resources and conduct law enforcement activities in the area.
While the encroachment was clear, Tarriela pointed out that it is still difficult for the country to carry out law enforcement against the maritime militia vessels.
"It's very difficult for us to categorize the Chinese fishing vessels. Are they just Chinese fishing vessels that are subject to fishery law enforcement or these are Chinese maritime militia which is part of a military establishment that can enjoy sovereign immunity," he explained.
The issue would boil down to the PCG's capability to chase away these ships that often come in swarms, he added.
Tarriela also explained that most of the time, the size of these Chinese fishing vessels or Chinese maritime militia has an overall length of at least 60 meters.
"We're talking about by 10s, 20s, 30s and we have a 44-meter coast guard vessel," he added.
Tarriela lamented that the only thing the country could do was to challenge these vessels using a radio "telling them to depart, and of course, patrolling those areas and reporting that to the NTF-WPS."
Hence, Malaya said it is critical for the Philippines to strengthen partnerships with like-minded countries and show China that "we have this network of alliances that support our position" as the rightful possessor of the WPS.
"We may not have sovereignty over it, but we have the right to exploit the natural resources. We allow freedom of navigation according to international law ngunit ang puwede lang makinabang sa EEZ ay ang Pilipinas (but the only one allowed to benefit from that EEZ is the Philippines)," Malaya said.