The Philippines said Monday it had summoned a Chinese envoy over "aggressive actions" by the China Coast Guard and other vessels near a reef off the Southeast Asian country's coast, while Beijing lodged its own complaint.
Deputy foreign ministers from the two countries later held a phone call in which China urged Manila to "pull back from the brink" and stop "provoking trouble at sea", Beijing said.
Beijing and Manila have a long history of maritime territorial disputes in the South China Sea and there have been repeated confrontations between their vessels near disputed reefs in recent months.
The latest incident took place Saturday near Second Thomas Shoal in the Spratly Islands during a regular Philippine mission to resupply Filipino troops garrisoned on the BRP Sierra Madre, a grounded navy ship.
The Philippines said the China Coast Guard blocked its supply vessel and damaged it with water cannon, injuring three soldiers.
The China Coast Guard has defended its actions, describing them as "lawful regulation, interception and expulsion" of a foreign vessel that "tried to forcefully intrude" into Chinese waters.
Manila conveyed its "strong protest against the aggressive actions undertaken by the China Coast Guard and Chinese Maritime Militia against the rotation and resupply mission undertaken by the Philippines in Ayungin Shoal," the Department of Foreign Affairs said on Monday, using the Filipino name for Second Thomas Shoal.
It said the Philippine embassy in Beijing also lodged a similar protest with the Chinese foreign ministry.
"In these demarches, the Philippines stressed, among others, that China has no right to be in Ayungin Shoal," the foreign affairs department said.
"The Philippines demands that Chinese vessels leave the vicinity of Ayungin Shoal and the Philippine exclusive economic zone immediately."
On Monday, China's embassy in the Philippines said it had complained to Manila over what it called the "illegal intrusion" of the Southeast Asian country's ships into its waters.
In the later phone call, Chinese vice foreign minister Chen Xiaodong said bilateral relations were "currently at a crossroads".
The Philippines must "pay serious attention to China's concerns, pull back from the brink, and return as soon as possible to the correct track of resolving differences with China through negotiation and consultation," Chen said.
Second Thomas Shoal is about 200 kilometres (120 miles) from the western Philippine island of Palawan, and more than 1,000 kilometres from China's nearest major landmass, Hainan island.
It is the same location where there have been recent collisions between vessels belonging to both countries, as well as water cannoning by the China Coast Guard.
- Cooling diplomatic relations -
China claims almost the entire South China Sea, brushing off rival claims from other countries including the Philippines and an international ruling that its assertion has no legal basis.
The United States, which has a mutual defence pact with Manila, has denounced the attack.
It came days after visiting US Secretary of State Antony Blinken said the United States stood by its "ironclad" commitments to defend longtime ally the Philippines against armed attack in the South China Sea.
Philippine Defence Secretary Gilbert Teodoro on Monday challenged Beijing to seek arbitration, which he said was the "best way of solving a legal dispute sustainably".
"That's why they don't like that," Teodoro told reporters.
Relations between Manila and Beijing have cooled under Philippine President Ferdinand Marcos as he seeks to deepen cooperation with the United States and regional neighbours, while standing up to Chinese aggression towards Philippine vessels.
Chinese and Philippine officials agreed in January on the need for closer dialogue to deal with "maritime emergencies" in the South China Sea, including Second Thomas Shoal.
But Manila said Monday that China's "aggressive actions call into question its sincerity in lowering the tensions and promoting peace and stability in the South China Sea."
Despite the attack, Philippine officials said the damaged vessel and a coast guard escort ship that came to its aid later deployed rigid-hull inflatable boats to deliver its cargo and personnel to the Filipino outpost.
Filipino soldiers stationed on the shoal live on the crumbling BRP Sierra Madre and require frequent resupplies for food, water and other necessities as well as transport for personnel rotations.
Apart from supplies and equipment, the Philippine military said six navy personnel were delivered to the BRP Sierra Madre on Saturday, replacing one soldier who was recently evacuated on medical grounds.
The damaged supply boat and its escorts sailed back to port after completing their mission, the task force said.