One Shell offshore drill rig is headed to Alaska and a second is poised to leave for Arctic waters. But Royal Dutch Shell still lacks final federal permits that would allow exploratory drilling and possible confirmation of rich oil reserves under the Chukchi Sea.

Mike LeVine, an attorney for Oceana, one of dozens of groups objecting to Arctic offshore drilling, says seeing Shell's flotilla sail north puts pressure on federal agencies to sign off on the permits.

The rigs were the target of protests when they docked in the Port of Seattle earlier this month.

Shell spokesman Curtis Smith says staging vessels for drilling before receiving all permits is not uncommon. It happened for Arctic drilling in 2007 and again in 2012.

Among the permissions Shell still needs are permits to drill from the government.