"China's solid macroeconomic fundamentals should continue to provide support for the currency," Matthew Ryan, senior market analyst at Ebury, said in a note.
The People's Bank of China (PBOC) set the midpoint rate at 6.5098 per dollar prior to the market open, 239 pips weaker than the previous fix of 6.4859.
"We look forward to the opportunity to lay out in very clear terms to our Chinese counterparts some of the concerns that we have about the actions they're taking," said Blinken.
On the mainland, the CSI300 index fell 0.4%, to 5,496.97 points at the end of the morning session, while the Shanghai Composite Index was unchanged at 3,596.10 points.
Investors are also concerned that Beijing could start tightening monetary policies amid a robust economic recovery and surging commodity prices, though analysts do not see any major policy reversals any time soon.