TikTok is suing the United States government in an effort to stop enforcement of a bill passed last month that seeks to force the app’s Chinese owner to sell the app or have it banned.

The lawsuit, filed Tuesday in the U.S. Court of Appeals for the D.C. Circuit, argues that the bill, the Protecting Americans from Foreign Adversary Controlled Applications Act, violates constitutional protections of free speech.

The suit calls the law an “unprecedented violation” of the First Amendment.

“For the first time in history, Congress has enacted a law that subjects a single, named speech platform to a permanent, nationwide ban,” TikTok wrote in the lawsuit, “and bars every American from participating in a unique online community with more than 1 billion people worldwide.”

The company argues that invoking national security concerns is not a sufficient reason for restricting free speech, and that the burden is on the federal government to prove that this restriction is warranted. It has not met that burden, the lawsuit stated.