BEIJING - China approved merger plans for six rare earth companies to optimize their industrial structure, the country's natural resources regulator said Thursday.

Merger plans of China Aluminum Corporation, Xiamen Tungsten Co LTd, Inner Mongolia BaoTou Steel Union Co Ltd, China Minmetals Corporation, Ganzhou Rare Earth Group Co LTd, and Guangdong Rare Earth Industrial Group Co LTd have been approved by authorities, according to an announcement released by the Ministry of Land and Resources.

The country's mining control limit for rare earth exploitation this year is 105,000 tons while that of tungsten concentrate stands at 91,300 tons, according to the announcement.