The United States and Japan are still the leading buyers of China's rare earths, even as other areas ramp up their production, a senior official said on Thursday.

For the first five months of this year, the US imported about 4,000 metric tons of rare earths from China, said Ma Rongzhang, secretary-general of the China Rare Earth Industry Association, during the Fifth China Baotou Rare Earth Industry Forum held in Baotou, Inner Mongolia autonomous region.

Japan came second with about 3,500 tons.

China's exports of rare earths have been increasing since February. Exports hit 2,196 tons in April, up 600 percent year-on-year and 38 percent more than the previous month.

However, prices remained subdues. Some major companies suggested the industry should reduce production to keep the prices at a reasonable level.