Aluminum Corp of China Ltd (Chalco), the top aluminium maker in the country, has idled 38%, or 4.11 million tons of its annual alumina capacity,  the Shanghai Securities News reported, citing Chalco's statement on Thursday.

The idled capacity includes 640,000 tons in its Zhongzhou plant, 1.1 million tons in Shanxi, 1.17 million tons in Shandong and 1.2 million tons in Henan.

Due to the weakening demand for aluminum products in both the domestic and overseas markets as well as the decreasing prices, the company decided to cut the alumina output in a bid to reduce the high operation cost.

The move came after the company's decision last month to cut electrolytic aluminum by 72 tons per year or 18% of Chalco's total capacity of the metal.

The company's net profit fell sharply by 92.03% year on year to RMB 182.90 million in the third quarter of this year due to higher raw material costs and lower selling price.