BEIJING, Aug. 24 -- China National Offshore Oil Corp.(CNOOC), China's largest producer of offshore oil and gas, said Monday that it had completed drilling of the country's first high-temperature, high-pressure deepwater exploration well.

The Lingshui 25-1S-1 deepwater well, drilled by CNOOC 981, the country's first deepwater drilling rig, is 140 kilometers south of Hainan Island, at a depth of 1 kilometer below sea surface and a temperature of over 150 degrees Celsius, the company said in a statement.

"The well [...] will solve problem we have faced with oil and gas exploration in the South China Sea," said Xie Yuhong, a manager with CNOOC.

Deepwater, high temperatures and high pressure have long held back oil and gas exploration in the South China Sea. More than half of the resources in the South China Sea are found in these environments.

CNOOC reported its first deepwater gasfield discovery below the South China Sea last August, which produces 56.5 million cubic feet of natural gas per day, equal to about 9,400 barrels of liquid oil per day.