MANILA — The Philippines has asked an international tribunal to declare China’s claims to virtually all the South China Sea invalid, saying Beijing’s actions have trampled other nations’ rights and irreversibly damaged vast coral reefs.

Foreign Secretary Albert del Rosario told the tribunal in The Hague on Tuesday that China’s strategy was to gradually take control of the strategic waters without sparking a crisis. Philippine officials provided his statement to journalists in Manila on Wednesday.

‘‘China’s positions and behavior have become progressively more aggressive and disconcerting,’’ Rosario told the tribunal. ‘‘Outside observers have referred to this as China’s ‘salami-slicing’ strategy: that is, taking little steps over time, none of which individually is enough to provoke a crisis.


‘‘When these small steps are taken together, however, they reflect China’s efforts to slowly consolidate de facto control throughout the South China Sea,’’ he said.

China’s aggressive moves, including preventing the Philippines from carrying out oil and gas explorations in what Manila considers its territorial waters and the forcible expulsion of Filipino fishermen from a disputed shoal, prompted Manila to take its conflict to international arbitration. Earlier attempts to resolve the conflict through negotiations, a step that China prefers, proved to be ineffective, Rosario said.

The tribunal opened hearings to address China’s contention that the five-person arbitration body operating under the United Nations Convention on the Law of the Sea does not have authority to assume jurisdiction over the Philippine complaints. The tribunal could proceed to look into the complaints against Beijing only if it rules that it has jurisdiction over the Philippine case.

‘‘China opposes any action made by the Philippines to initiate and push ahead with the arbitration,’’ Chinese Foreign Ministry spokeswoman Hua Chunying said in a news conference in Beijing Tuesday, adding Manila reneged on an agreement not to take such unilateral steps.


Philippine officials have denied that there was such an agreement, saying Beijing has clearly agreed in the past to resolve the disputes on the basis of international law, including the 1982 United Nations convention, which allows coastal states to exclusively exploit resources within 200 nautical miles of waters from their territory.

China’s ambassador to Manila, Zhao Jianhua, has said his government could not be compelled to follow any decision by the arbitration tribunal, adding Beijing would remain open to negotiations with the Philippines to resolve the disputes.

‘‘The result of the arbitration is not binding as our side is concerned. This is the legal right of China,’’ he told reporters last month.

China, the Philippines, Brunei, Malaysia, Vietnam, and Taiwan have been contesting ownership of the resource-rich South China Sea. Washington and other countries have expressed concern over China’s increasingly assertive actions, including massive island building that they say has damaged vast coral reefs in the disputed waters. Beijing said fears it would eventually limit freedom of navigation and air flights are unfounded.