Beijing, Jun 1 (IANS/EFE): China has saved the equivalent of 6 million tonnes of petroleum over the past five years since prohibiting supermarkets and other stores from providing customers with free plastic bags and banning the manufacture and use of bags thinner than .025 millimeters, authorities said.

Those measures adopted June 1, 2008, have caused consumption to drop by 67 billion plastic bags, or by more than two-thirds, Xinhua news agency quoted Li Jing, deputy director of environmental policy at the National Development and Reform Commission, or NDRC, as saying Friday.

Saturday marks the five-year anniversary of those policies, which the world's second-largest economy adopted to save energy and bolster environmental protection, as well as improve the country's image in the months prior to the 2008 Olympic Games in Beijing.

Since then, the production of bags thinner than 0.025 mm - once a common sight at Chinese supermarkets and department stores - is prohibited in the Asian nation and store owners are required to charge customers a small fee for thicker plastic bags.

Li, however, acknowledged that authorities have not succeeded in completely eradicating stores' use of ultra-thin plastic bags and said tighter supervision is needed.

The ban led to the shuttering of the leading plastic-bag factory in China, which generated more than 3 million tonnes of plastic garbage annually before it went into effect.