The U.S. appealed a court ruling that temporarily blocked President Donald Trump’s ban on the viral video-sharing app TikTok.

A federal judge granted a preliminary injunction against the ban on new downloads of TikTok on Sept. 27, saying it was likely the Trump administration had exceeded its legal authority. The government began the process of appealing on Thursday, filing a notice of appeal in court in Washington.

The Trump administration has called for a ban on the grounds that TikTok’s Chinese ownership makes the app a national security threat. The proposed ban on new downloads would have removed TikTok from stores run by Apple Inc. and Google’s Android, the most widely used marketplaces for apps. People who didn’t yet have the app wouldn’t have been able to get it, and those who already had it wouldn’t have access to updates needed to ensure its safe and smooth operation.

A parallel effort by the Trump administration to ban the Chinese-owned social-media app WeChat has also been blocked in court. The U.S. appealed that ruling last Friday.