Washington state will sue President Donald Trump over his executive order banning immigration from seven Muslim-majority countries, the state’s attorney general Bob Ferguson announced Monday. The suit would make Washington the first state to sue over the executive order. “If successful it would have the effect of invalidating the president’s unlawful action nationwide,” Ferguson said during a Monday press conference, adding that the suit would name Trump, the U.S. Department of Homeland Security, and members of the Trump administration as plaintiffs. The suit, which calls parts of the anti-refugee order unconstitutional, will be filed in a Seattle high court on Monday. Washington is also calling for a temporary restraining order on the ban's enforcement, which would allow the state to protect people currently affected by the order.