The People's Bank of China set the midpoint rate at 6.5646 per dollar prior to market open, 0.5 percent weaker than the previous fix of 6.5314, the biggest fall between daily fixings since the yuan's benchmark devaluation in mid-August.

The spot market opened at 6.5750 per dollar and was changing hands at 6.5811 in early trade, 256 pips away from the previous close and 0.25 percent away from the midpoint. The spot rate is currently allowed to trade with a range 2 percent above or below the official fixing on any given day.

The offshore yuan was trading 2.36 percent weaker than the onshore spot at 6.74 per dollar.

(Reporting by the Shanghai Newsroom; Editing by Eric Meijer)