"The utter disregard by the Chinese Embassy in Manila of international law especially the UNCLOS to which China is a party is appalling. Its nine-dash line claim is without any factual or legal basis. This, together with its so-called historical claim, was flatly and categorically rejected by the arbitral tribunal," the Phillipine official said in a statement.

"The Philippines’ claims stand on solid ground, while China’s do not.

China should respect Philippine sovereignty over the Kalayaan Islands, and its sovereign rights over its Exclusive Economic Zone as defined by UNCLOS and affirmed by the arbitral award,"  Delfin Lorenzana said.

"The continued presence of Chinese maritime militias in the area reveals their intent to further occupy features in the West Philippine Sea. They have done this before at Panatag Shoal or Bajo de Masinloc and at Panganiban Reef brazenly violating Philippine sovereignty and sovereign rights under international law," the official said.

"As a party to the DOC, China should refrain from conducting activities that disturb regional and international peace and security," Lorenzana said.

The Philippines’ air force has been conducting daily aerial patrols over Chinese fishing vessels which have been spotted near the disputed Whitsun Reef, media reports said.

The diplomatic row was touched off earlier this month when some 220 boats were first spotted at the boomerang-shaped Whitsun Reef, west of Palawan Island, reports Al Jazeera.

The Philippines ordered China to recall the vessels, describing their presence as an incursion into its sovereign territory.

But China, which claims almost the entirety of the South China Sea, said the flotilla is made up of fishing vessels sheltering from bad weather, reports the news channel.