China's manufacturing business activity slightly expanded in May, indicated by a Purchasing Managers Index reading of 50.2, up from 50.1 in April, according to official data.

The reading has remained above 50, the separation between contraction and expansion, for three consecutive months and suggested a slow rebound of the real economy, said a statement from the National Bureau of Statistics.

The manufacturing PMI sub-components were more positive than the headline, with the new orders and production showing more meaningful rebounds, up by 0.4 and 0.3 points respectively in May from April. The employment sub-index also improved last month, the NBS data showed.