MANILA, Philippines (AP) -- The Philippines took a desperate legal step against China's claims to virtually the entire South China Sea, formally notifying the Asian superpower that Manila is seeking international arbitration to declare Beijing's moves in the potentially oil-rich waters "unlawful."
Foreign Secretary Albert del Rosario said Tuesday his department summoned Chinese Ambassador Ma Keqing and handed her a note notifying the Chinese government that the Philippines is bringing the countries' conflicting claims to a tribunal operating under the 1982 U.N. Convention on the Law of the Sea. It wants the panel to declare Beijing's moves in the potentially oil-rich waters unlawful.
"The Philippines has exhausted almost all political and diplomatic avenues for a peaceful negotiated settlement of its maritime disputes with China," del Rosario told a news conference. "To this day, a solution is still elusive."
Six governments have overlapping claims across the vast South China Sea, with China claiming it has sovereignty over virtually all of it. Chinese paramilitary ships confronted Philippine vessels last year in a monthslong standoff over a shoal that both countries claim.
There are fears that territorial conflicts in the region, including a dispute between Japan and China in the East China Sea, could spark Asia's next armed conflict.
Chinese Embassy spokesman Zhang Hua said Ma responded by reiterating that "China has indisputable sovereignty over the islands in the South China Sea and its adjacent waters." Zhang said the ambassador stressed that the disputes should be settled by the rival claimants through one-on-one negotiations.
U.N. Secretary-General Ban Ki-moon said in New York that the United Nations "if necessary, if requested, is ready to provide technical and professional assistance."
"But primarily, all these issues should be resolved by the parties concerned," he said, adding that it was important for the countries in the region to resolve disputes "through dialogue in a peaceful and amicable way. "
China, the Philippines' third-largest trading partner, doesn't like to see its sovereignty or its claims of sovereignty questioned and has regularly and vociferously opposed attempts to involve third parties or world bodies in the South China Sea disputes, fearing that would weaken its hand.
The Philippines hopes that arbitration through an international tribunal would lead to a ruling that China's sprawling claims violate the U.N. sea convention, or UNCLOS. China and the Philippines are among more than 160 countries that have ratified the accord, which aims to govern the use of offshore areas and sets territorial limits for coastal states.
Del Rosario said the Philippines hopes the tribunal will order China to "desist from activities that violate the rights of the Philippines in its maritime domain."
But even if a tribunal rules against China, Beijing could choose to ignore the ruling.
Chen Shaofeng, an international affairs expert at Peking University, said no arbitration should proceed unless both parties approve it. He said it is unlikely that Beijing would agree to such a process, or accept the results of a tribunal it did not recognize.
"There is no precedent in Chinese history of China allowing international arbitration on territorial disputes no matter over land or waters," Chen said. "The Philippines knows its proposal for arbitration will get nowhere in the end, but it just wants to make the issue more internationalized."
Philippine diplomats, however, argue that the arbitration can proceed even without China's involvement.
In the note delivered to the Chinese ambassador, the Philippines listed several aggressive moves it alleged were launched by China in recent years to fortify its territorial claims, including the occupation of South China Sea islands and the enactment of a Chinese law that allows Chinese patrol vessels to block and board foreign ships passing through vast stretches of waters that Beijing claims.
The Philippines specifically sought an end to Chinese occupation and activities on eight reefs and shoals and surrounding waters, including Mischief Reef, which China occupied in 1995, sparking fierce protests from Manila and concern from Southeast Asian nations.
In June, after a monthslong bitter standoff, China wrested control of what it calls Huangyan island, and what the Philippines calls Scarborough Shoal, without firing a shot.
With a typhoon approaching, both sides agreed to withdraw their ships. But China quickly returned and strung up a cable across the lagoon to keep Philippine vessels out.
Del Rosario's office said in a statement that Philippine leaders are "all for improving our economic relations with China but it should not be at the expense of surrendering our national sovereignty," adding that it hopes Manila's action will not have an adverse effect on trade between the countries.
Del Rosario said the Philippines' move was made independently of the United States, its treaty ally. China has warned the United States to stay away from the disputes, but Washington has declared that the peaceful resolution of the conflicts and freedom of navigation in the contested waters are in the U.S. national interest.
Associated Press writers Hrvoje Hranjski in Manila and Charles Hutzler in Beijing contributed to this report.
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