China National Offshore Oil Corp, the country's largest offshore oil and gas developer, released its 2013 Sustainability Report on Monday in Beijing, detailing the company's efforts to improve clean energy development and realize its environmental commitment both in domestic and overseas markets.

This is the ninth year the company has released an annual sustainable report.

According to the report, the company produced 11.1 billion cubic meters of natural gas in 2013, among which 10.67 billion cu m came from offshore production, the company's major strength.

It imported 13.01 million metric tons of liquefied natural gas last year.

In the last eight years, CNOOC has imported more than 50 million tons of LNG, which has greatly helped the country's clean energy supply.

"As a responsible company, CNOOC has been following the green development mode and puts the sustainable development concept into its daily operation and strategy planning," Lyu Bo, vice-general manager of the company, said at a press briefing on Monday.

"The company's energy supply ability has been greatly increased through exploration efforts on domestic and overseas energy resources," he said.

After CNOOC acquired Nexen Inc, it has continued support for research and activities focused on environmental protection, technological development and community support in the local area, the report said.

The company retained all of the management and employees of Nexen after the transition. CNOOC also supported oil sand research by the University of Alberta in Canada.

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