BEIJING (Reuters) – As Asia’s biggest security summit is set to convene, China on Friday accused the Philippines of seeking to negate its sovereignty in the South China Sea by describing Taiping Island as a reef and not an island in Manila’s territorial court case.

Tensions in the South China Sea are set to dominate the Shangri-La Dialogue (SLD) starting Friday, exposing a deepening rivalry between the United States and China ahead of a landmark legal ruling over the disputed area in the Hague.

Beijing refuses to recognize the case lodged by the Philippines with the Permanent Court of Arbitration in The Hague over territorial claims in the South China Sea and says such disputes should be resolved through bilateral talks.

Manila is challenging the legality of China’s claim there, in part by arguing that no land mass in the Spratly archipelago, including Itu Aba, known as Taiping Island in Chinese, can legally be considered a life-sustaining island.

That would mean it cannot hold rights to a 200 nautical mile (370 km) exclusive economic zone.

“The Philippines’ attempt to define Taiping Island as a ‘reef’ exposes that the goal of its arbitration case is to try to negate China’s sovereignty and related rights over the Spratly Islands,” China’s Foreign Ministry spokeswoman Hua Chunying said.

“This is a violation of international law and completely unacceptable,” Hua said in a statement posted to the ministry’s website.

Chinese fishermen had historically lived on Itu Aba year-round, and fished, dug wells, cultivated plants and constructed buildings, all evidence that it was an island capable of sustaining human life and economic activity, Hua said.

China claims almost the entire South China Sea, through which about $5 trillion worth of ship-borne goods passes every year. Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims to the waters.

Self-ruled Taiwan controls Itu Aba, which some analysts believe has the strongest claim to island status and an economic zone. Late last year it finished a $100 million port upgrade on Itu Aba, which has an airstrip, a hospital and fresh water.

China, which claims sovereignty over Taiwan, has appeared unruffled by Taiwan’s upgrading work on Itu Aba. Military strategists say that is because it could fall into China’s hands should it ever take over Taiwan.

Taiwan in May called on the international court not to make a ruling on the legal status of Itu Aba in the South China Sea case if the judges don’t visit first to see for themselves it can sustain life.

(Reporting by Michael Martina; Editing by Michael Perry)