Beijing warned Manila on Tuesday not to "stir up trouble" after the Philippine Coast Guard said it had removed a floating barrier at a disputed reef that was allegedly deployed by China to block Filipinos from the traditional fishing ground.

Scarborough Shoal in the South China Sea has long been a source of tension between the countries. China seized the ring of reefs from the Philippines in 2012 and has since deployed patrol boats to keep out Filipino fishermen.

The latest spat was sparked by a 300-metre (328-yard) floating barrier that was found across the entrance of the shoal last week during a routine Philippine government resupply mission to Filipino fishermen plying the waters near the shoal.

The Philippines condemned the installation and its coast guard announced on Monday that it had "successfully" removed the barrier from the reef, which Manila calls Bajo de Masinloc, in a special operation ordered by President Ferdinand Marcos.

Chinese foreign ministry spokesman Wang Wenbin hit back on Tuesday, saying Beijing "firmly upholds the sovereignty and maritime rights and interests of the Huangyan island", referring to the shoal by its Chinese name.

"We advise the Philippines not to provoke or stir up trouble," Wang added.

- 'Well within rights' -

Philippine National Security Adviser Eduardo Ano responded to the warning by saying his country was "well within its rights" to remove any barrier at the reef.

China claims sovereignty over almost the entire South China Sea, despite a 2016 international court ruling that its stance has no legal basis.

Scarborough Shoal sits 240 kilometres (150 miles) west of the Philippines' main island of Luzon and nearly 900 kilometres from the nearest major Chinese land mass of Hainan.

Under the 1982 United Nations Convention on the Law of the Sea, which China helped negotiate, countries have jurisdiction over the natural resources within about 200 nautical miles (370 kilometres) of their shore.

The Philippine Coast Guard released a video on Monday showing a man wearing snorkelling gear using a knife to sever a rope attached to white buoys, while another showed an anchor being hauled from the water into a wooden outrigger boat.

"Upon checking with our intelligence operatives in Bajo de Masinloc, the Chinese government removed already the barrier," Jay Tarriela, Philippine Coast Guard spokesman for the West Philippine Sea, told local media Tuesday.

The floating barrier had prevented fishing boats from entering the shoal's shallow waters where fish are more abundant.

Philippine officials previously accused the Chinese coast guard of installing the barrier before a Bureau of Fisheries and Aquatic Resources resupply ship arrived at the shoal last Wednesday.

The Philippine foreign ministry said on Monday it would "take all appropriate measures to protect our country's sovereignty and the livelihood of our fisherfolk", without elaborating.