With pressure building on Shell's port activity in Seattle, an Alaskan energy coalition said the state's economy won't be held hostage by external activists.

"We don't like our economy being held hostage by activists from another state," Anne Seneca, president of the Consumer Energy Alliance-Alaska, said in a statement.

With federal approval in hand, Shell said it may start its drilling campaign in the arctic waters off the coast of Alaska as early as this summer. Shell's drilling rig, Polar Pioneer, is stationed at the Port of Seattle ahead of the program's start. In mid-May, a flotilla of kayakers took to the waters off the coast of Seattle to protest Shell.

Advocacy group Friends of the Earth launched a legal challenge against the federal Bureau of Ocean Energy Management for approving Shell's exploration program.

"We argue that the agency failed to include potentially significant environmental effects, such as marine mammal distribution and habitat use, and failed to assess the particular risks of a large oil spill during the exploratory phase," the group said in a statement.

Shell is proposing as many as six wells in a region known as the Burger prospect, located in shallow waters, using the Noble Discoverer and Polar Pioneer rigs.

Its drillship Kulluk struck ground off the Alaskan coast in 2012, and the U.S. Coast Guard blamed harsh winter conditions and the company's efforts to escape Alaskan tax laws for the incident.

The Consumer Energy Alliance said it had the support of 13 other state organizations and 19 Alaskan lawmakers in backing Shell's plans. With nearly 90 percent of the state revenue coming from energy resources, the coalition said the arctic program is critical to the success of the Alaskan economy.

Alaska Gov. Bill Walker toured the Polar Pioneer drilling rig last week, saying arctic drilling "will happen."