LOS ANGELES, United States (AFP) — The top prosecutor in the state of Washington filed a lawsuit on Monday challenging as illegal and unconstitutional President Donald Trump’s travel ban on seven Muslim-majority countries and demanding an immediate halt to its implementation.

“No one is above the law — not even the president,” Attorney General Bob Ferguson told a news conference. “And in the courtroom, it is not the loudest voice that prevails. It’s the Constitution.”

Ferguson’s lawsuit — the first of its kind — targets Trump, Homeland Security and high-ranking administration officials. It calls for key provisions of the president’s executive order on immigration to be declared illegal and unconstitutional.

The complaint argues that the travel ban, which has been met with an uproar both in the United States and abroad, was separating and harming families “and undermining Washington’s sovereign interest in remaining a welcoming place for immigrants and refugees.”

Several major companies in Washington state, including Amazon and Expedia, filed declarations alongside the lawsuit explaining the fallout of the executive order on their operations and employees.

“Never has our system of checks and balances been more important,” said Washington governor Jay Inslee, who joined Ferguson at the press conference.

“Until Congress takes this administration to task for the obvious moral and legal injuries suffered by innocent, law-abiding people entering our country, it is up to states to protect and promote the rights of the people who reside in our borders.”

The suit urges the court to schedule a hearing on the matter within two weeks.

On Saturday, a federal judge in New York blocked Trump’s order as it pertained to certain individuals affected by the travel ban.

Ferguson’s lawsuit is broader in scope as it seeks to invalidate entire sections of the executive order.