LONDON, May 10 (Reuters) - Britain's economic output grew by a stronger-than-expected 0.6% in the three months to March after entering a mild recession in the second half of last year, data from the Office for National Statistics showed on Friday.

A Reuters poll of economists had pointed to a 0.4% expansion of gross domestic product in the January-to-March period.

(Reporting by Suban Abdulla; Editing by Kate Holton)