Corrected 1:18 p.m. | The Commerce Department on Friday said it was banning two popular apps owned by Chinese companies, with one of them being prohibited as soon as Sunday.

The department said the messaging app WeChat, which is mostly used by Chinese within their country and by some in the diaspora in the United States and around the world, would be banned starting Sunday. And also starting Sunday, TikTok won’t be available in an app store. A complete ban on TikTok, prohibiting use even from current users, will take effect Nov. 12.

Commerce Secretary Wilbur Ross said the actions followed President Donald Trump’s executive order of Aug. 6 that announced the administration’s intent to ban the two apps.

The department said the apps collected “vast swaths of data from users, including network activity, location data, and browsing and search histories” and that the companies provide the information to Chinese authorities, including its intelligence services, “creating unacceptable risks to our national security.”

As of Sunday, any provision of service to distribute or maintain WeChat or TikTok would be banned, and any use of WeChat to transfer money between users or processing payments within the United States would be banned, the department said.

Starting on Sunday for WeChat and on Nov. 12 for TikTok, hosting services and content delivery would be banned, the department said.

TikTok’s owner, ByteDance, has denied allegations that it shares users’ data with Beijing. The company last week submitted a plan to the Treasury Department offering to partner with tech giant Oracle Corp. and has promised to open a U.S. headquarters potentially employing 20,000 people. The partnership announcement came after weeks of talks about selling the U.S. portion of TikTok to Microsoft Corp. It’s unclear how the Commerce Department’s ban would affect the proposed partnership between ByteDance and Oracle.

Appearing on Fox Business Network, Ross said WeChat would essentially be shut down by Monday, and the tens of millions of U.S. users of TikTok won’t have access to software updates and maintenance for the app.

It’s unclear if Google, Apple and other U.S. tech companies that have opposed such bans would sue the administration over the prohibitions.

Correction: This report was revised to reflect the correct timing of the ban on downloads from app stores.