New Delhi, May 22 -- India's private sector gained momentum in May, led by a sharp acceleration in services activity, as strong demand from both domestic and international markets drove business expansion and hiring, according to the HSBC Flash India PMI survey released Thursday.

Compiled by S&P Global, the survey also signalled a revival in business confidence, the first uptick since January.

The HSBC Flash India Composite Output Index, which captures activity across both manufacturing and services, is estimated to have risen to 61.2 in May from 59.7 in April, indicating robust expansion. A reading above 50 denotes growth, and the index has now remained in expansion territory for over three years.

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