BEIJING -- China's central bank pumped cash into the financial system through open market operations Tuesday to maintain liquidity in the market.

A total of 200 billion yuan (about $31.22 billion) was injected into the market via medium-term lending facility (MLF), according to the People's Bank of China, the central bank.

The funds will mature in one year at an interest rate of 2.95 percent. The operation included a rollover of MLF funds that are expected to mature Tuesday, the central bank said.

The central bank also injected 10 billion yuan into the market through seven-day reverse repos at an interest rate of 2.2 percent.

The move was intended to maintain reasonable and ample liquidity in the banking system, the central bank said.

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.

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.