A Chinese frigate aggressively tailed a Philippine warship in a disputed part of the South China Sea.

Footage shows the Chinese vessel shadowing the Philippine Navy's BRP Emilio Jacinto (PS35) some 11.8 nautical miles off the contested Scarborough Shoal, on May 5.

China Coast Guard vessel 5403 and another Chinese ship with bow number 573 later attempted to cross the Philippine corvette's bow to obstruct its path.

The Philippine military said the navy ship was on a joint patrol with the Philippine Coast Guard and fisheries bureau when China carried out the 'high-risk manoeuvre'.

In a statement, the Armed Forces of the Philippines said: 'These reckless actions not only posed a direct threat to the safety of navigation of PS35, but also violated the International Regulations for Preventing Collisions at Sea (COLREGs).

'The Armed Forces of the Philippines expresses its serious concern over these irresponsible actions by Chinese maritime forces. Such threatening and provocative conduct can lead to misunderstanding that may escalate tensions and impact regional stability.'

China has been sending numerous coast guard vessels near the shores of the Philippines on maritime patrol.

Authorities believe the ships were deployed to intimidate Filipino fishermen from entering the Scarborough Shoal, a disputed fishing ground and resource-rich area in the South China Sea.

Expansionist China currently lays claim over almost the entire South China Sea, one of the world's busiest sea lanes. But a United Nations-backed tribunal in 2016 deemed its claims groundless.

The Communist rogue state - accused of genocide for its crimes against the Uyghur population - has been steadily increasing its influence in recent years through investment in developing countries.