BEIJING - China is to regulate its lead-zinc industries to cool down investment in the sector, China's state authority has said.

The National Development and Reform Commission (NDRC) and eight other authorities jointly issued a circular on Wednesday announcing six entries of measures to curb oversupply.

According to the circular, China will tighten market access to the lead-zinc industry by ensuring companies that are qualified in production safety, environmental protection and resource and energy consumption.

The circular said the government will strengthen its management of the import and export of lead and zinc products by improving tariff policies, but specific details were not released.

One hundred and sixty-nine lead-zinc smelting projects are under construction in China, with a total investment of 12.5 billion yuan (US$1.56 billion). When they start operation, the annual output of lead and zinc products will rise by 1.9 million tons and 2.9 million tons, respectively, according to the circular.

China has pledged to limit the annual output of refined lead to below 4 million tons and that of zinc to below 5 million tons, the circular said. In 2005, China produced 5 million tons of lead products and 3.4 million tons of zinc products.