Russian officials say up to 2,000 tons of oil has been spilled at the Trebs oil field in the northern Nenets Autonomous district.
The local environmental agency says the spill began on April 20 during work on an exploratory well.
The agency said the oil was gushing from the well for nearly two days before workers managed to cap it on April 22.
Emergency Ministry officials in Moscow maintain that they were able to control the oil spill.
The environmental agency said it will prepare a lawsuit against the oil companies after the clean-up operation is completed.
Based on reporting by AP and upi.com