The Vietnamese government and state-owned PetroVietnam have objected to drilling operations by China National Offshore Oil Corp. in the South China Sea, saying that a rig owned by the Chinese company is in Vietnamese waters.
Vietnam's foreign ministry spokesman Le Hai Binh said Sunday that CNOOC's deepwater rig Haiyang Shiyou 981 had been dispatched into Vietnam's waters.
"Any activity conducted by foreign countries in Vietnam?s waters without its permission is illegal and has no value," Binh said in a government statement.
Binh's response was to a notice issued by China's Maritime Safety Administration on May 3, which said the rig would be operating within a one-mile radius of 15-29.58N/111-12.06E for "South China Sea drilling work" from May 2 to August 15 this year.
Binh said the location identified in the notice was "totally within Vietnam's exclusive economic zone and continental shelf, about 120 miles from its coast."
The drilling area overlaps Vietnam's block 143 and is 119 miles off the Vietnamese central coast, PetroVietnam-run Petrotimes daily said in a report Sunday.
The acreage is located near Vietnamese blocks 118, 119 and 144. The first two blocks were previously awarded to ExxonMobil and the third to Murphy Oil by PetroVietnam.
PetroVietnam said it had sent a letter of protest to CNOOC and requested it to stop its operations and move the rig away from Vietnamese waters, according to the statement by the Vietnam government.
CNOOC could not be contacted for comment Monday.
The Haiyang Shiyou 981 semi-submersible rig is CNOOC's first wholly owned deepwater drilling rig and is operated by the company's subsidiary China Oilfield Services Limited. The rig is capable of drilling in water depth of 3,000 meters. CNOOC said in January that it planned to drill a total 155 exploration wells this year, but did not say how many of those would be deepwater ones.
This is the latest boundary dispute in the South China Sea. Relations between both countries hit a low point in mid-2012 when CNOOC offered nine oil and gas blocks for foreign cooperation in the South China Sea in an area south of Hainan in waters that Vietnam considers as part of its exclusive economic zone, sparking protests from Hanoi and PetroVietnam. No companies bid on the blocks.
Later the same year, Chinese fishing vessels cut the cables of PetroVietnam's seismic ship Binh Minh 02, which had been operating outside the Gulf of Tonkin -- known in China as the Beibu Gulf -- again sparking protests by Vietnam.