The Philippine Coast Guard (PCG) reportedly shadowed a Chinese ship sailing in rough conditions in the South China Sea.

The PCG's BRP Cabra ship followed China Coast Guard (CCG) vessel 3105 as it travelled 95 nautical miles off the coast of Zambales province, on March 8.

Footage shows the Filipino ship sounding its horn to warn the CCG amid churning waves that swelled up to 16ft.

In a statement, PCG spokesman Commodore Jay Tarriela said: 'The BRP Cabra has effectively kept the larger vessel at a distance of more than 95 nautical miles off the coast of Zambales, preventing its approach to the coastline.

'PCG Commandant Admiral Ronnie Gil Gavan has made it clear that the deployment of PCG vessels aims to persistently prevent China from altering the status quo and normalizing its unlawful presence within the Philippines' Exclusive Economic Zone.'

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

One of them is the massive CCG 5901, the world's largest coast guard vessel at 541 feet and 12,000 tons, which started lurking off the seaside province of Zambales on January 4 afternoon.

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.