LONDON, April 25 (Reuters) - Harbour Energy has started production at the Tolmount gas field in the British North Sea, a source close to the company said on Monday.

Harbour operates and holds a 50% stake in the field along with Dana Petroleum.

The field, whose start-up was initially planned in the first quarter of the year, is expecte to reach peak production of 40,000 barrels of oil equivalent per day.

(Reporting by Ron Bousso, Editing by Louise Heavens)