Philippine boats in South China Sea blocked by coastguard

Chinese ships used water cannons on two supply boats in disputed area

A dilapidated Philippine Navy ship with Philippine troops on board is anchored off Second Thomas Shoal, known locally as Ayungin Shoal, on March 30, 2014, in the South China Sea. AP

Chinese coastguard ships have blocked two Philippine supply boats heading to a disputed shoal occupied by Filipino marines in the South China Sea.

The Chinese ships used water cannons on the supply boats, provoking an angry protest to China and a warning from the Philippine government that its vessels are covered under a mutual defence treaty with the US, Manila’s top diplomat said on Thursday.

Philippine Foreign Secretary Teodoro Locsin Jr said no one was hurt in the incident in the disputed waters on Tuesday, but the two supply ships had to abort their mission to provide food supplies to Filipino forces occupying the Second Thomas Shoal, which lies off western Palawan province in the Philippines’ internationally recognised exclusive economic zone.

Mr Locsin said in a tweet that the three Chinese coastguard ships’ actions were illegal and he asked them “to take heed and back off”.

The Philippine government has conveyed to China “our outrage, condemnation and protest of the incident”, Mr Locsin said. He said “this failure to exercise self-restraint threatens the special relationship between the Philippines and China” that President Rodrigo Duterte and his Chinese counterpart, Xi Jinping, have worked hard to nurture.

There was no immediate comment from Chinese officials in Manila or Beijing.

The incident is the latest flare-up in the long-simmering territorial disputes in the strategic waterway, where China, the Philippines, Vietnam, Malaysia, Brunei and Taiwan have overlapping claims.

China claims virtually the entire waterway and has transformed seven disputed shoals into missile-protected island bases to cement its claims, ratcheting up tensions and alarming rival claimants and western governments led by the US.

Washington has no claims in the busy waterway but has patrolled the region with its Navy ships and aircraft to assure its allies, including the Philippines, and ensure freedom of navigation and overflight. China has repeatedly warned the US to stay away from the disputed waters and not meddle in what it says is a regional issue.

President Joe Biden and his predecessor Donald Trump have repeatedly assured the Philippines the US will honour its obligation under the two nations’ Mutual Defence Treaty if Philippine forces, ships or aircraft come under attack in the long-disputed region.