Central Huijin Investment Ltd spent 2.8 billion yuan ($446.21 million) to increase its stakes in four of China's biggest lenders in the fourth quarter of last year, according to the banks' annual report released recently.

According to an announcement in October 2012, Central Huijin's plan to increase its stakes on the four banks would last for six months, which means the investment company will buy more shares before April.

Central Huijin is an investment company owned by the central government, and is also a wholly owned subsidiary of China Investment Corporation.

According to the annual report of the Bank of China, Central Huijin bought 247 million shares of the lender, and holds 97 percent of all the lender's shares that were publicly offered in A-share market by the end of 2012.

Also, according to the lender's annual report, Central Huijin bought 207 million shares of Industrial and Commercial Bank of China Ltd, the world's biggest lender by market value, in the fourth quarter of 2012.

In the same quarter, the investment company also bought 170 million shares of China Construction Bank and 215 million shares of Agricultural Bank of China.

wuyiyao@chinadaily.com.cn