BEIJING, March 1 (Reuters) - Activity in China's manufacturing sector expanded faster than expected in February, an official survey showed on Wednesday.

The official Purchasing Managers' Index (PMI) rose to a three-month high of 51.6 in February, compared with the previous month's 51.3, and above the 50-point mark that separates growth from contraction on a monthly basis.

Analysts polled by Reuters had predicted a reading of 51.1, pointing to a modest expansion as China's industrial firms continued to benefit from higher sales prices and a recovery in demand fueled by a construction boom.

(Reporting by Beijing Monitoring Desk; Editing by Kim Coghill)