China's central bank continued its net cash injections via open market operations on Friday, the fourth straight day after a halt on Monday.

The People's Bank of China (PBOC) conducted 100 billion yuan (about 14.5 billion U.S. dollars) of reverse repos, a process by which the central bank purchases securities from banks through bidding, with an agreement to sell them back in the future.

The injection saw a net 40 billion yuan pumped into the market today, offset by 60 billion yuan in maturing reverse repos.

The operations included 60 billion yuan of 7-day reverse repo prices to yield 2.45 percent, 20 billion yuan of 14-day contracts with a yield of 2.6 percent, and 20 billion yuan of 28-day agreements with a yield of 2.75 percent.

China's monetary policy in 2017 is set to be "prudent and neutral," keeping appropriate liquidity levels and avoiding large injections.