File photo of China's central bank

BEIJING, March 18 -- China's central bank on Friday pumped more money into the market to ease liquidity strain.

The People's Bank of China (PBOC) conducted 110 billion yuan(16.9 billion U.S. dollars) of seven-day reverse repurchase agreements (repo), a process in which central banks purchase securities from banks with an agreement to resell them in the future.

The reverse repo, the largest single-day operation this month, was priced to yield 2.25 percent, unchanged from Thursday's injection of 40 billion yuan, according to a PBOC statement.

The move follows a week-long rise in money-market rates as commercial lenders start to hoard cash to meet quarter-end regulatory reserves.

In Friday's interbank market, the benchmark overnight Shanghai Interbank Offered Rate (Shibor), which measures the cost at which Chinese banks lend to one another, climbed by 2 basis points to1.99 percent, the highest level this month.