BEIJING, June 7 -- The central bank pumped 208 billion yuan (about 32 billion U.S. dollars) into the financial system on Tuesday in open market operations via medium-term lending facility(MLF).

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

The fresh funds were injected into 14 financial institutions, according to the People's Bank of China (PBOC).

A total of 123.2 billion yuan is for three-month MLF, 11.5 billion yuan is for six-month MLF, and 73.3 billion yuan is for one-year MLF, at interest rates of 2.75 percent, 2.85 percent and 3 percent, respectively.

The interest rates were left unchanged to "guide financial institutions to boost support for key areas and vulnerable links in the national economy," the central bank said.