China, Philippines trade accusations over collision in South China Sea

China and the Philippines traded accusations over a collision in disputed waters of the South China Sea as Chinese vessels blocked a Philippine boat supplying forces there on Sunday, the latest in a series of maritime confrontations.

The two countries have had numerous run-ins in areas of the South China Sea in recent months, especially the disputed Second Thomas Shoal, part of the Spratly Islands.

The Philippines has been sending supplies to troops stationed on a rusted World War Two-era transport ship used as an outpost on the shoal, prompting China's coast guard to repeatedly deploy vessels to block the resupply missions.

In the incident on Sunday morning, China's coast guard said there had been a "slight collision" between one of its ships and the Philippine boat while the coast guard was "lawfully" blocking the boat from transporting "illegal construction materials" to the warship.

Manila responded by condemning "in the strongest degree" the "dangerous blocking manoeuvres" of the Chinese vessel.

China's "dangerous, irresponsible and illegal actions" were "in violation of Philippine sovereignty, sovereign rights and jurisdiction", Manila's Task Force for the West Philippine Sea said in a statement.

The United States expressed support for the Philippines, denouncing China's "disruption of a legal Philippine resupply mission".

"We stand with our #FriendsPartnersAllies in protecting Philippine sovereignty and in support of a #FreeAndOpenIndoPacific," Ambassador to the Philippines MaryKay Carlson posted on X, the platform previously called Twitter.

Manila's relations with Beijing have soured under President Ferdinand Marcos Jr., who has strengthened military engagement with Washington since taking office last year. The Pentagon said in May it would protect the Philippines if its coast guard came under attack "anywhere in the South China Sea".

Beijing claims sovereignty over almost the entire South China Sea, including parts of the exclusive economic zones of the Philippines, Vietnam, Malaysia, Brunei and Indonesia. The Permanent Court of Arbitration in 2016 said China's claims had no legal basis.

Last week, the Philippine military demanded China stop its "dangerous and offensive" actions after a Chinese navy ship shadowed and attempted to cut off a Philippine navy vessel conducting a resupply mission.

China had warned the Philippines against further "provocations", saying such acts violated its territorial sovereignty.

Sunday's collision occurred during a routine resupply mission of a boat contracted by the Philippine armed forces, Manila said.

"The provocative, irresponsible, and illegal action" of the Chinese coast guard vessel "imperilled the safety of the crew" of the Philippine boat, the task force said.

China's coast guard said in a statement the Philippine vessel had ignored repeated warnings, crossed the bow of the Chinese ship and "deliberately provoked trouble", causing the collision.

"The Philippines behaviour seriously violates the international rules on avoiding collisions at sea and threatens the navigation safety of our vessels," the coast guard said.

Manila grounded the BRP Sierra Madre warship in 1999 as part of its sovereignty claim to the Second Thomas Shoal, which lies within its 200-mile exclusive economic zone.