Updated

A federal judge has ordered Greenpeace protesters to stay away from Royal Dutch Shell PLC ships.

U.S. District Court Judge Sharon Gleason on Friday also prohibited Greenpeace from flying unmanned vehicles over the offshore Arctic area where Shell plans to drill.

The safety-zone injunction is in effect until Oct. 31, the Alaska Dispatch News reported. Shell Offshore Inc. sued on April 7, one day after six Greenpeace protesters boarded the Blue Marlin, a heavy-lift ship carrying a Transocean Ltd. semi-submersible drilling unit, the Polar Pioneer, as it crossed the Pacific.

The injunction establishes buffer zones from 300 feet to about 5,000 feet for all of Shell's Chukchi Sea fleet, anchor lines and buoys attached to ships.

Shell wants to drill this summer in the sea off Alaska's northwest coast to determine whether there are commercial quantities of oil and gas. Arctic offshore reserves are estimated at 26 billion barrels of recoverable oil and 130 trillion cubic feet of natural gas, according to U.S. Geological Survey estimates.

Shell said it was pleased with the injunction.

"We cannot condone Greenpeace's unlawful and unsafe tactics. Safety remains paramount," Shell said in a statement.

Greenpeace called the ruling disappointing.

"Instead of saying Greenpeace can't go near Shell, our government should be saying Shell can't go near the Arctic," Greenpeace spokesman Travis Nichols said in a statement.

Meanwhile in Seattle, Shell wants to park two massive Arctic oil drilling rigs in the waterfront, but it has to get around protesters in kayaks and the city's mayor.

Seattle Mayor Ed Murray on Monday said the Port of Seattle must get a new permit before it can host Shell's drilling fleet. The mayor urged the port to reconsider its two-year, $13 million lease with Foss Maritime, a company that has been in Seattle for more than a century and whose client is Shell.

The 400-foot-long Polar Pioneer is in Port Angeles, Washington, but will head to Seattle sometime in the coming weeks.

Protesters plan to converge by land and in kayaks during a three-day "festival of resistance" starting May 16.

Once the rigs are in Seattle, some say they will do what they can to prevent the fleet from leaving to explore for oil.