The Petroleum Safety Authority of Norway said Statoil can use the Transocean rig for around 28 days, depending on whether or not a discovery is made.
The well in the Pingvin license area is about 180 miles north of the Norwegian coast in 1,300 feet of water.
More than a dozen Greenpeace demonstrators took part in a protest against Statoil's drilling plans for arctic waters by boarding the Transocean rig in May. Around half of them surrendered their campaign voluntarily and Statoil said the seven activists who remained behind were arrested by Norwegian police.
Greenpeace said its demonstrators were there to raise awareness about the risks associated with drilling in hard-to-reach and pristine locations like the Barents Sea.
The government said Statoil is restricted from drilling into any oil-bearing layer in the well before Sept. 5.
"This condition has been set to allow for appeals before the riskiest part of the operation gets under way," the safety authority said.