SEATTLE (AP) _ Foss Maritime plans to appeal Seattle’s position that Royal Dutch Shell can’t use the Port of Seattle’s Terminal 5 under the existing permit.

The company says it intends to provide its customer, Shell, with the services it needs to prepare to explore for oil in Alaska.

Royal Dutch Shell has been planning to base its fleet at Terminal 5 for six months each year when it’s not exploring for oil in the Arctic. But Seattle Mayor Ed Murray threw a wrench into those plans on Monday when he said the port can’t host Shell’s offshore Arctic fleet until it gets a new land-use permit.

“I expect the port to obtain all required city permits before any moorage or works begins at T5 on off-shore oil drilling equipment,” Murray said in a statement. “While requiring a new permit may not stop the port’s plans, it does give the port and opportunity to pause and rethink this issue.”

Murray said that in order to lessen the damage of climate change, “it’s time to turn the page on things like coal trains, oil trains and oil drilling rigs.”

Foss spokesman Paul Queary responded to the mayor’s announcement by saying that when the company entered into a lease with the port, Foss was assured that the project was covered by the existing permit.

Foss released a statement late Friday announcing the appeal and saying that the city’s position is not supported by the permit’s plain language.

“By taking this action so late in the day, Mayor Ed Murray is trying to stop a lawful project that has already put 417 people to work full-time and will soon employ hundreds more, many of them citizens of Seattle,” the statement said. “Worse, he has openly solicited the Port of Seattle to use the city’s action as a pretext to break a valid lease at Terminal 5, despite the separately elected Port Commission’s recent unanimous vote to uphold the lease.

“These actions are an attempt to prevent one of the city’s oldest and most prominent companies from performing marine services that it has provided and the Port has welcomed for generations. This action is akin to the mayor ordering Seattle City Light to cut off all electricity to Amazon on the Friday after Thanksgiving.”

Foss plans to appeal to the Seattle Hearing Examiner in the next two weeks. Once filed, the examiner will set a hearing date and then issue a ruling.