U.S. lawmakers want to force a sale of TikTok by its Chinese owner or ban it from app stores, which legal experts said would set up a showdown with the social media company over the U.S. Constitution's First Amendment free speech protections.

While the bill itself does not say anything about speech, the proposal has alarmed civil rights advocates, TikTok and users of the app, all of whom could sue to block the proposal if it becomes law.

Legal experts said opponents of the law could argue it infringes free speech by preventing users from expressing themselves and businesses from using the app to promote their products. TikTok has already beaten back a similar attempt to ban its use in the U.S. state of Montana, although the state is appealing that ruling.