BEIJING - China's service sector activity expanded in March, but at a slower pace, an official monthly survey showed on Wednesday.

The purchasing managers' index (PMI) for the non-manufacturing sector dipped to 53.7 in March from 53.9 in February, according to a report released jointly by the National Bureau of Statistics and the China Federation of Logistics and Purchasing.

A reading above 50 indicates expansion, while a reading below 50 represents contraction.

China's non-manufacturing PMI mainly tracks the business activities of the services and construction sectors.

The service sector sub-index fell to 52.3 in March from 51.4 one month earlier.

Services such as retailing, catering and air transportation that were booming during the China Lunar New Year holiday in February waned last month, said Zhao Qinghe, an NBS senior statistician.

The sub-indices of business activities and new orders for the construction industry in March both rose 2.4 percentage points to 58.9 and 54.7, respectively.

The expansion of activities in the sector expanded was due to rising temperature and the construction of major infrastructure projects picking up speed, Zhao added.