BEIJING — Deep Sea No 1, China's first self-operated 1,500-meter deep-water gas field, started production on June 25, according to the China National Offshore Oil Corporation (CNOOC).

The operation of the gas field, 150 kilometers off the city of Sanya in South China's island province of Hainan, marks the country's capability of ultra deep-water drilling for oil and gas, compared with the 300-meter depth previously, said the CNOOC.

Production at the gas field, detected in 2014, is of great significance to ensuring national energy security, optimizing the country's energy structure and promoting regional economic development, said the CNOOC.

Deep Sea No 1 marks important progress in the country's deep-water exploration and development of oil and gas, which indicates China's great potential and broad prospects in the area, according to an official with the National Energy Administration.

The gas field is expected to provide a total of 3 billion cubic meters of natural gas per year.

The exploration, development, construction and operation of the Deep Sea No 1 gas field has driven the development of shipbuilding, steel, electromechanical and other industries.