Cheng Lian, a senior financial analyst at the major think tank for the Chinese government, said that without the firewall of the yuan's inconvertibility under the currency account, an over-concentrated payment and settlement system would expose the economy to greater financial risks than a scattered and diversified system.

According to the report, State-owned banks' contribution to total capital flows dropped to 36 percent by the end of 2011 from the 44 percent in 2007, while that of urban commercial banks rose from 7 to 10 percent.

"Although China is likely to witness the rapid development of the payment and settlement sector, especially driven by e-commerce, a more modernized system would have some negative influence on the monetary authorities and affect the effectiveness of policies," said Zhang Chengsi, a professor of finance at Renmin University of China.

He said it might add to market complexity by enlarging the money multiplier and introducing more liquidity risks.

Wu Xuchuan, a division head at the central bank's research bureau, said the development of the payment and settlement market would pose a challenge to the central bank, which should respond to this by adjusting monetary policy targets and strengthening regulation in a timely manner.