New reports from The Philippines and Vietnam reveal that China is building a network of artificial islands in the disputed Spratly archipelago in a bid to bolster its territorial claims. It’s the latest development in the saber-rattling exercise quietly simmering in the South China Sea. The Philippines released photos of newly built sand cays, arguing that China will use them as bases in their push to control the area.

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The Spratlys are one of many disputed island chains and reefs in the South China Sea to which multiple countries currently lay claim. In April, the Philippines filed a protest with China for its land reclamation activities on two reefs. This month, the Philippines’ president, Benigno S. Aquino III, has complained of Chinese ship movements in the territory, which he claims are being used for the construction of artificial islands at two other locations.

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The Philippines and Vietnam are concerned about China’s artificial island building because the nation could claim a 200-mile exclusion zone around any ground under the United Nations Convention on the Law of the Sea, even if the land mass is remarkably new. New islands could allow China to install surveillance centers with permanent staff and supply stations for ships, increasing the range of its vessels.

China counters that it is entitled to do as it likes in its territory. Last month, Foreign Ministry spokesperson Hua Chunying stated: “China has indisputable sovereignty over Nansha Islands.” Nansha is the Chinese name for the archipelago. Given that China seized Johnson Reef, one of the construction sites, from Vietnam in 1988, not everybody agrees that the situation is so cut and dried. The latest construction activity comes after China installed an oil rig in the disputed Paracel Islands near Vietnam last month, and can only raise tensions in the region even further.

Via The New York Times

Photos via Clayton Dube and Andrew Chubb via Twitter; map via KAVO via Wikimedia Commons