China's central bank pumped a net amount of 210 billion yuan ($31.1 billion) into the country's banking system via open market operations during the last week to maintain liquidity at a reasonable level.

The People's Bank of China (PBOC) injected 480 billion yuan into the markets via reverse repo operations from Sept 14 to 18, and drained 620 billion yuan from the markets as the same amount of reserve repo agreements matured.

A reverse repo is a process in which the central bank purchases securities from commercial banks through bidding, with an agreement to sell them back in the future.

During the same period, a total of 600 billion yuan was injected into the market via medium-term lending facility (MLF) while 200 billion yuan of MLF matured.

The MLF tool was introduced in 2014 to help commercial and policy banks maintain liquidity by allowing them to borrow from the central bank using securities as collateral.

Meanwhile, 50 billion yuan of the time deposits of commercial banks for central treasury cash management matured on Friday.

China has vowed to pursue a prudent monetary policy in a more flexible and appropriate way. The central bank said in its second-quarter monetary policy report that it will make monetary policy more flexible and targeted to achieve a long-term balance between stabilizing growth and preventing risks.