Manila summoned Beijing’s ambassador on Monday over two collisions between Philippine and Chinese vessels in the disputed South China Sea, a foreign ministry official said. 

The countries have traded blame over Sunday’s incidents near Second Thomas Shoal in the Spratly Islands, with both sides releasing videos to support their accusations.

The two collisions happened during a routine Philippine resupply mission to Filipino troops stationed on a navy vessel grounded on the shoal to assert Manila’s territorial claims.

“We’re making full use of diplomatic processes… available to us. That includes summoning the Chinese ambassador (Huang Xilian), which we did this morning,” foreign ministry spokeswoman Teresita Daza told reporters.

Daza said the ambassador was unavailable and was represented by his deputy chief of mission during the meeting at the foreign ministry.

Xilian was last summoned to the foreign ministry in August after the China Coast Guard used water cannon on Philippine vessels near Second Thomas Shoal.

“Ayungin Shoal is part of our exclusive economic zone and continental shelf and we have sovereign rights and jurisdiction over it,” Daza said, using the Philippine name for the shoal.

“China, as a major power, bears a heavier responsibility of contributing to peace and stability in the region,” she said.

The Philippines has accused a China Coast Guard vessel of “reckless manoeuvres” that led to a collision with a wooden boat contracted by the Armed Forces of the Philippines to deliver provisions to troops on the BRP Sierra Madre.

China said the “slight collision” happened after the resupply boat ignored “multiple warnings and deliberately passed through law enforcement in an unprofessional and dangerous manner”, state broadcaster CCTV reported Sunday, citing the foreign ministry.

In another incident, a Philippine coastguard vessel escorting the routine resupply mission was “bumped” by what the Philippine task force described as a “Chinese Maritime Militia vessel”.

China, however, accused the Philippine boat of “deliberately” stirring up trouble by reversing in a “premeditated manner” into a Chinese fishing vessel.

China claims almost the entire South China Sea, through which trillions of dollars in trade passes annually, and has ignored an international ruling that its assertion has no legal basis.

Second Thomas Shoal is about 200 kilometres (124 miles) from the western Philippine island of Palawan, and more than 1,000 kilometres from China’s nearest major landmass, Hainan island.

As China moves ever more confidently to assert its claims to sovereignty over the waters, officials and experts have warned of the potential for collisions.

The Philippine Navy deliberately grounded the World War II-era BRP Sierra Madre on Second Thomas Shoal in 1999 to check China’s advance in the waters.

The troops stationed on the crumbling ship depend on regular supply deliveries for their survival.

The Philippines has outposts on nine reefs and islands in the Spratlys, including Second Thomas Shoal.