BEIJING, May 12. /ITAR-TASS/. China has urged Vietnam to ensure security of Chinese individuals and companies working on disputed islands in the South China Sea.

The Foreign Ministry’s comments come after Sunday protests in several Vietnamese cities demanding that China winds up oil exploration on a rig near islands known both as the Paracels and in China as the Shisha archipelago, claimed as historically Chinese territory.

Protests focused on the activities of the Haiyang Shiyou drilling rig in the waters, in which China claims it has been working for a decade. Foreign ministry official Hua Chunying said on Monday that the rig was operating in China’s territorial waters.

China was closely watching the developments and urged Vietnam to take necessary steps to provide security of Chinese citizens and companies on its territory, the spokesperson said. This echoed an earlier ministry’s statement saying that the HD-981 installation was legal as China deemed the archipelago its own territory.

Beijing has long been on uneasy terms with many countries in the region as to territorial allegiance of the Nansha (Spratly), Shisha (Paracel Islands) and Huang Yan islands (Scarborough Reef) in the South China Sea, where experts expect large offshore oil reserves.

Countries involved in the dispute are Brunei, Vietnam, Malaysia, Taiwan and the Philippines. China asserts its “indisputable” sovereignty over the islands.