LONDON - Royal Dutch Shell says a leak at one of its North Sea oil rig has been reduced to 2 barrels, or 84 gallons, a day.
Glen Cayley, technical director of Shell's European exploration and production activities, says the company deeply regrets the spill, Britain's worst in a decade.
He says an investigation is under way to determine the cause of the spill, which was first noticed Wednesday.
The company estimated Monday that 54,600 gallons of oil had spilled into the North Sea from the rig off Scotland's eastern coast, and the leak was continuing at 5 barrels a day.
The Gannet Alpha oil rig, 112 miles (180 kilometres) east of the city of Aberdeen, is operated by Shell and co-owned by Shell and Esso, a subsidiary of the U.S. oil firm Exxon Mobil.