TikTok filed a federal lawsuit on Monday against Montana after the state passed a law banning the short-video app.

"We are challenging Montana’s unconstitutional TikTok ban to protect our business and the hundreds of thousands of TikTok users in Montana," TikTok said in the court filing.

(Reporting by Jasper Ward and David Shepardson in Washington, writing by Paul Grant; editing by Eric Beech)