The central parity of the Renminbi (RMB), or China's currency yuan, weakened to 6.7733 per U.S. dollar on Monday from Friday's 6.7720, according to the data released by the China Foreign Exchange Trading System.

Last Friday, the central parity of RMB against the U.S. dollar rose to 6.7720, the strongest since China announced to unpeg the yuan from the U.S. dollar in July 2005.

China's central bank announced on June 19 that it would further the reform of the formation mechanism of the yuan exchange rate to improve its flexibility.