Spokesman Mike Townsley says the environmental group will now pursue legal efforts to force Cairn to release its confidential plans for coping with an oil spill, which Greenpeace claims are inadequate.

The Scottish company could not immediately respond Friday.

Cairn has said it would use a second rig to drill a relief well in a scenario similar to the BP disaster last year in the Gulf of Mexico.

Twenty Greenpeace activists were arrested last week after scaling Cairn’s 53,000-ton Leiv Eiriksson rig off Greenland’s west coast.