LONDON (REUTERS) - Britain is grappling with a potential gas supply crisis as a late blast of winter depletes stored reserves, coal power plants close and pending maintenance in Norway threatens to further squeeze supply.

The country risks running out of stored gas by April 8 based on the fall in its reserves seen since the cold hit at the beginning of March, Reuters calculations show. Gas storage sites have been depleted by 90 per cent, with the equivalent of less than two days' consumption remaining, data from Gas Infrastructure Europe shows.

If the cold persists then, the UK may need to cut gas supplies to some big industrial customers, as it did in 2010 at a time of severe gas shortages.

The Department of Energy and Climate Change (DECC) said it was monitoring the situation closely.

"Our market has spare import capacity built in. However, we take gas security and the risk of harmful price spikes seriously and monitor price and supply developments working closely with National Grid," said Emily Towers, DECC's spokeswoman responsible for energy supply and emergency planning.

"We are working with (the regulator) Ofgem to review our market arrangements ...At the same time, we are diversifying our energy mix to reduce our dependence on imported fossil fuels and putting in place policies to cut energy demand." The rapid depletion of gas storage sites has prompted operator Centrica, Britain's biggest power and gas provider, to restrict withdrawals owing to falling reservoir pressure, in a sign of the growing strain on the system.