CALGARY - Shares in Calgary-based Husky Energy Inc. (HSE.TO) fell by as much as 7.7 per cent on Thursday morning after operations aboard its SeaRose FPSO vessel off the Newfoundland and Labrador coast was ordered suspended by the federal-provincial regulator because of a close call with an iceberg last March.

Husky shares fell as low as $17.58 from Wednesday's close of $19.06.

The Canada-Newfoundland and Labrador Offshore Petroleum Board said Wednesday after markets closed the vessel would be suspended from operating until it is sure that "corrective and appropriate actions" have taken place.

It said the floating production, storage and off-loading vessel with 84 people and 340,000 barrels of crude onboard failed to follow protocol and sail away when an iceberg entered its 0.25-nautical-mile ice exclusion area, adding personnel at one point were instructed to muster and 'brace for impact.'

Barclays analysts said in a note Thursday the suspension is "significant" because it cuts off about 27,000 barrels per day of some of the most profitable production in Husky's oil and gas portfolio for an undetermined length of time.

That's about eight per cent of total oil and gas production from the company, which also operates in Western Canada and the Asia Pacific region.