BEIJING (Reuters) - Chinese maritime officials on Friday removed an online notice giving the location of a $1-billion (700.62 million pounds) deepwater oil rig in the South China Sea two days after issuing it, following a warning from Vietnam about drilling in disputed waters.
Vietnam closely tracks the movement of the oil rig, which in mid-2014 caused the worst diplomatic rift between the neighbours in decades, when China parked it for 10 weeks in waters Vietnam considers its own.
Annual trade between the communist neighbours exceeds $60 billion (42.04 billion pounds) but anti-China sentiment is strong in Vietnam, where people are embittered over what many see as a history of Chinese bullying and territorial infringements in the South China Sea.
On Friday, China's Maritime Safety Administration cancelled, and then removed from its website, the notice dated January 20.
The notice placed the Haiyang Shiyou 981 rig at the Lingshui 25-2-1 well site about 140 km (87 miles) south of China's Sanya resort city on Hainan island, and 150 km (93 miles) west of the Paracel Islands that China occupies, and which Vietnam claims.
The agency was not immediately available to comment.
Still on display is a notice from December placing the rig at the Lingshui 24-1-1 well site, about 170 km (106 miles) southeast of Sanya, and 70 km northwest (44 miles) of the Paracel Islands.
The December notice originally said the rig would remain there until February 10.
On Wednesday, China's Foreign Ministry said the rig was not drilling in disputed territory, in response to a warning from Vietnam to refrain from such activity.
China Oilfield Services Ltd (COSL), a subsidiary of China National Offshore Oil Corporation (CNOOC), manages the platform and rents it out.
CNOOC's flagship listed subsidiary, CNOOC Ltd, said last year it had discovered a mid-sized volume of natural gas at the Lingshui 25-1 well, near the Lingshui 25-2 well site. That followed discovery of a larger volume at the Lingshui 17-2 well, 30 km (19 miles) west of Lingshui 24-1-1.
The company could not immediately be reached for comment.
In 2014, China's deployment of the rig about 120 nautical miles off Vietnam's coast, in what Vietnam considers its exclusive economic zone, led to the worst breakdown in relations since a brief border war in 1979.
Vietnam's concern follows its complaints, echoed by the Philippines, over China's recent test flights on an artificial island in the disputed Spratly archipelago.
China considers most of the South China Sea to be its territory but Brunei, Malaysia, the Philippines, Taiwan and Vietnam have competing claims. About $5 trillion in ship-borne trade passes through the busy waterway each year.