China's central bank on Friday strengthened the yuan currency against the US dollar by 0.05%, the national foreign exchange market said, ending three days of falls after a surprise devaluation.

The daily reference rate was set at 6.3975 yuan to $1.0, up from 6.4010 the previous day, the China Foreign Exchange Trade System said. The rate was also slightly higher than Thursday's close of 6.3982 yuan.