The US Supreme Court heard arguments Friday about whether or not to uphold a law that effectively bans the social media app TikTok. The law was signed last year and calls for the app to be sold by its Chinese parent company ByteDance by Sunday, and the app could be shut down in the US if the law is upheld.

TikTok will shut down entirely in the US on Sunday without intervention from the US Supreme Court, unnamed sources have told Reuters. That would go beyond the ban’s requirement for app stores to stop offering downloads of the app, but not immediately halt use of it.

(Reuters) -TikTok plans to shut its app for U.S. users from Sunday, when a federal ban on the social media app could come into effect, unless the Supreme Court moves to block it, sources familiar with the matter said.