Business activity in China's non-manufacturing sector expanded at slower pace in April, official data showed on Sunday.

The purchasing managers' index (PMI) for the non-manufacturing sector stood at 53.5 in April, down from 53.8 in March and well above the 50 mark that separates expansion and contraction, according to data released jointly by the National Bureau of Statistics (NBS) and the China Federation of Logistics and Purchasing.

The non-manufacturing PMI tracks business activities of both the service sector and the construction industry, Xinhua news agency reported.

The service sector sub-index was 52.5 in April, down 0.6 points from March, said the report.

Businesses related to storage, tourism, accommodation, and telecommunications posted sound growth in April. However, wholesale, catering, insurance and repairing industries reported a drop in business volumes.

The sub-index for service new orders declined 2.4 points from one month earlier to 48.4 in April, suggesting slower demand in the non-manufacturing sector.

The sub-index for construction activity rose 1.4 points to 59.4 in April, while that for new orders was down 0.5 point to 50.