(Recasts, adds comments from minister)
BEIJING, Jan 7 (Reuters) - China will step up its controls over the mining of rare earths and release new industry standards to cut pollution, a minister and media said on Friday, after the world's biggest supplier cut export quotas for the minerals.
China, which produces about 97 percent of the global supply of the vital metals, slashed its export quota by 35 percent for the first half of 2011 compared with a year earlier, saying it wanted to conserve reserves and protect the environment. [ID:nTOE6BT00S]
China will "strengthen the supervision and management of mineral resources mining ... and deepen control over rare earth mining capacity and extraction", Minister of Land and Resources Xu Shaoshi said on a webcast on the ministry's website (www.mlr.gov.cn). He did not elaborate.
Xu added that China's campaign against illegal rare earths mining and effort to better manage the industry had achieved "notable results".
Meanwhile, new environmental standards, described as "stringent" by an expert who helped draft the rules, would limit the amount of permissible pollutants in each litre of waste water, the official China Daily said.
Under the rules, expected to pinch rare earths miners with raised environmental protection costs, levels of ammonia nitrogen would be cut from 25 milligrams to 15 milligrams per litre, and radioactive elements and phosphorus emissions would be reduced.
The new regulations could be formally unveiled as soon as February after being approved by China's Ministry of Environmental Protection in December, the China Daily said.
It added that China was considering the creation of a rare earth industry association and a governmental unit to prevent more mining abuses.
China has said other countries should share the burden of mining the metals. Illegal mining practices and over-exporting rare earths have hurt China's environment and depleted its resources, it says.
But China's quotas have sparked tension with global importers of the metals, and the United States has threatened to take a complaint to the World Trade Organization, which judges international trade disputes.
Japan's trade minister said this week he wanted to visit China this month to talk to officials there to secure enough rare earths, which are vital to make electronics and clean energy technology including computers, wind turbines and electric cars. [ID:nTOE70402F] (Reporting by Michael Martina; Editing by Ben Blanchard)