China's net foreign exchange purchase was 128.25 billion yuan ($20.71 billion) in February, the latest statistics from the central bank showed on Tuesday.

But the net forex purchases fell sharply from 437.4 billion yuan in January, hitting their lowest point since September 2013.

Sun Junwei, China economist for HSBC Holdings Plc, said the drop reflects the impact of China's adjustment of the yuan's exchange rate.