The Trump administration said Friday that it will block people in the United States from downloading popular Chinese-owned apps TikTok and WeChat starting Sunday night. Both apps are used by over 100 million people in the country.

According to a US Department of Commerce order, new downloads of the apps will be banned from US app stores as of Sept. 20. WeChat, an app popular with Chinese nationals in the United States, will also be banned from hosting content, processing payments within the US, and sending money to other WeChat users in the country among other restrictions. TikTok will face similar restrictions starting on Nov. 12, which means that existing users will no longer be able to access TikTok videos after that date.

If you already have TikTok downloaded on your phone, it will continue to work at least until Nov. 12.

“The Chinese Communist Party (CCP) has demonstrated the means and motives to use these apps to threaten the national security, foreign policy, and the economy of the U.S.,” a press release from the Commerce Department stated. “Each collects vast swaths of data from users, including network activity, location data, and browsing and search histories. Each is an active participant in China’s civil-military fusion and is subject to mandatory cooperation with the intelligence services of the CCP. This combination results in the use of WeChat and TikTok creating unacceptable risks to our national security.”

“Today’s actions prove once again that President Trump will do everything in his power to guarantee our national security and protect Americans from the threats of the Chinese Communist Party,” Commerce Secretary Wilbur Ross said in a statement.

TikTok said that it did not agree with the administration. “We disagree with the decision from the Commerce Department, and are disappointed that it stands to block new app downloads from Sunday and ban use of the TikTok app in the US from November 12,” said a TikTok spokesperson in a statement. “Our community of 100 million US users love TikTok because it’s a home for entertainment, self-expression, and connection, and we’re committed to protecting their privacy and safety as we continue working to bring joy to families and meaningful careers to those who create on our platform.

The statement further added:

In our proposal to the US Administration, we’ve already committed to unprecedented levels of additional transparency and accountability well beyond what other apps are willing to do, including third-party audits, verification of code security, and US government oversight of US data security. Further, an American technology provider would be responsible for maintaining and operating the TikTok network in the US, which would include all services and data serving US consumers. We will continue to challenge the unjust executive order, which was enacted without due process and threatens to deprive the American people and small businesses across the US of a significant platform for both a voice and livelihoods.”

Apple and Google did not respond to a request for comment.

In early August, Trump signed an executive order declaring TikTok as a “national emergency,” saying that it would be effectively banned from the country in 45 days unless a US company bought its American operations. Last month, ByteDance, the Beijing-based company that owns TikTok, sued the Trump administration and challenged the ban in a federal court.

TikTok’s interim US CEO Vanessa Pappas tweeted on Friday morning asking tech companies like Facebook to support the company’s litigation.

ByteDance was initially in talks with Microsoft to sell its US operations, but a deal did not come through. ByteDance has since been in conversations with software maker Oracle and Walmart to create a new company, TikTok Global, to assuage the Trump administration’s concerns over people’s data. The deal, however, has not yet been finalized.

Oracle did not respond to a request for comment. A Walmart spokesperson pointed BuzzFeed News to a statement the company issued last week, which said that it was still in talks with ByteDance.

The Commerce Department’s press release said that TikTok had until Nov. 12 to resolve the Trump administration’s concerns, and if it did, it could be allowed back into app stores.