An oil spill was observed on 23 November near the Transocean Arctic rig which is drilling on the Statoil-operated Norne satellites in the Norwegian Sea. Statoil immediately began monitoring it by helicopter.
A first estimate of the size of the discharge, based on observations from the helicopter, indicated a volume of some 280 barrels (45 cubic metres) of oil.
The spill is now dissolving. Statoil does not consider there to be any risk of the oil reaching land.
Modification work is being carried out on the Norne ship, and it would appear that the discharge is connected to the shutdown of the facilities on board.
Statoil is working to identify what has happened and why.
The ship will not resume production following the modification work until a thorough overview of the cause of the spill is ready.
An internal inquiry into the incident has been launched by Statoil.
The spill has been reported to the Petroleum Safety Authority Norway.