WASHINGTON — The Trump administration said Friday it would bar the Chinese-owned mobile apps WeChat and TikTok from U.S. app stores as of Sunday, striking a harsh blow against two popular services used by more than 100 million people in the United States.
The restrictions will ban the transferring of funds or processing of payments through WeChat within the United States as of Sunday. In the case of WeChat, the restrictions will also prevent any company from offering internet hosting, content delivery networks, internet transit or peering services to WeChat, or using the app’s code in other software or services in the United States.
Those same prohibitions on providing services go into effect on Nov. 12 for TikTok.
“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.
The actions follow an Aug. 6 executive order by the president, in which he argued that TikTok and WeChat collect data from American users that could be accessed by the Chinese government. The administration has threatened fines of up to $1 million and up to 20 years in prison for violations of the order.
TikTok is currently in talks to be acquired by the American software maker Oracle, and could announce a deal that assuages the administration’s national security concerns. In its announcement, the Commerce Department said that the president had given until Nov. 12 for TikTok’s national security concerns to be resolved, and if they were, the prohibitions in the order could be lifted.
TikTok spokesman Josh Gartner said in a statement that the company was disappointed in the Commerce Department’s decision.
“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 U.S. of a significant platform for both a voice and livelihoods,” he said.
Tencent and Oracle did not immediately respond to requests for comment.
Mr. Ross, in an interview on Fox Business Network on Friday morning, said that the ban would initially have a much greater impact on WeChat.
“For all practical purposes it will be shut down in the U.S., but only in the U.S., as of midnight Monday,” Mr. Ross said.
TikTok would also face some changes, but would still be allowed to function until Nov. 12, Mr. Ross said, at which point it would face the same ban as WeChat if there was no deal that satisfied the administration’s concerns.
“As to TikTok, the only real change as of Sunday night will be users won’t have access to improved updated apps, upgraded apps or maintenance,” he said.
That delay will allow users of the popular social media app — who are primarily young — to continue using the service ahead of the Nov. 4 election. TikTok has increasingly become a political force, with its users posting in support of their favored candidates and offering commentary on current events. It has also been utilized as a political tool — hundreds of teenage TikTok users claimed credit for low turnout at a rally for Mr. Trump in Tulsa, Okla., earlier this year.
The actions take aim at two of China’s most popular and successful tech exports, which knit together nearly two billion people worldwide.
TikTok, which is owned by Chinese company ByteDance but does not directly operate in China, has become a wildly popular platform for sharing viral videos in the United States. WeChat, which is owned by Tencent Holdings, functions as a chat app, a payment platform and a news source for people in China and the Chinese diaspora around the world. It is also a conduit for Chinese propaganda and surveillance.
As of Friday morning, the Chinese government had not issued any statements, and it was not immediately clear if China would retaliate. China has long blocked access to such American social media as Twitter, Facebook and WhatsApp that it cannot readily monitor or censor.
The prohibitions raise the question of whether Google and Apple, the major operators of American app stores, could sue the administration.
Tech companies have made clear that they don’t like the idea of blocking apps without a more organized policy process, and have suggested that they see this as a First Amendment issue, said Adam Segal, a cybersecurity expert at the Council on Foreign Relations.
Mr. Segal said it was not entirely clear why the administration had chosen to go after these two Chinese services, and not other similar ones. “A lot of it just feels to me to be improvisational,” he said.
Apple and Google did not immediately respond to requests for comment. But both have said in the past that they comply with the local laws in each country they serve.
In a call with reporters Friday, a senior official with the Commerce Department pushed back on the idea that a ban would curtail Americans’ freedom of speech, saying that the administration had chosen to target these apps in part because they are used to censor speech.
“We are not China. We are not attempting to censor speech. In fact, it’s the exact opposite,” the official said.
Mr. Ross portrayed the threat from the apps in stark terms, likening it to a window between the U.S. and China that allows Beijing to peer into the everyday lives of Americans.
“What they collect are data on locality, data on what you are streaming toward, what your preferences are, what you are referencing, every bit of behavior that the American side is indulging in becomes available to whoever is watching on the other side,” he said. “That’s what we’re trying to squelch.”
In its announcement, the Commerce Department said that both WeChat and TikTok collected information from their users including location data, network activity and browsing histories. As Chinese companies, they are also subject to China’s policy of “civil-military fusion” and mandatory cooperation with Chinese intelligence services, it said.
Cybersecurity experts have debated the extent to which the bans would address national security threats. Many other Chinese-owned companies gather data from mobile users in the United States, as do Facebook, Google and other non-Chinese services.
James Lewis, a senior vice president at the Center for Strategic and International Studies, said the administration’s moves seemed aimed at pushing ByteDance to give the U.S. more control over TikTok.
“It looks like it’s largely a continuation of the pressure tactics to get ByteDance to make a deal,” said Mr. Lewis. “WeChat is sort of the human sacrifice of this deal. They’ve gone nuclear on them.”
The ability of the U.S. to enforce the ban also remains an open question. A Commerce Department official declined to discuss enforcement on Friday. He said that the administration hoped to work with American tech companies, saying that “every company that this touches is becoming increasingly aware of the challenges that these applications pose.”
The Commerce Department said the government’s focus would not be on policing individual users, but gradually limiting the ability of the apps to operate in the United States over time. According to Commerce, the rule changes mean WeChat’s functionality will begin to degrade as of Sunday, while TikTok’s will be unchanged until after Nov. 12.
Apple and Google regularly remove apps from their app stores for a variety of reasons, including security flaws, violations of the companies’ rules and, in some places, requests from the government.
In China, Apple has appeared to pull thousands of apps from its App Store in the country under orders from the government, including certain gaming apps and news apps, including The New York Times’s app. Last year, Apple removed an app from its App Store in Hong Kong that helped protesters there track police after it was criticized by Chinese state media for the app.
And in Russia, the messaging app Telegram complained in 2018 that Apple removed it there because of the app’s dispute with the Russian government.
Because of Apple and Google’s dominance of the smartphone market — they make the software that backs nearly all the world’s smartphones — governments can target the companies to try to roll out such bans, which otherwise could prove tricky to enforce given the open nature of the internet.
Apple has especially been used as a tool by governments because it only allows apps and software to be downloaded onto iPhones via its App Store. That means forcing Apple to remove an app would effectively stop any new user from downloading it.
People who already have the app on their phones can continue to use it. Yet eventually the app will become obsolete on those phones because the app’s developer will not be able to update it to make it compatible with updates Apple and Google make to their smartphone software.
On Google’s Android software, users can download apps and software from outside of its official Google Play Store. That means requiring Google to pull an app from the Play Store would only create a hurdle for some users to downloading that app on Android devices.
Android underpins most of the world’s smartphones, in part because of its dominance in many developing countries like India, but Apple and Google roughly split the U.S. market.
Doug Jacobson, a partner at the trade law firm Jacobson Burton Kelley, said that it would be up to Google and Apple to remove the apps from their stores. The two companies could face civil or criminal penalties for failing to comply with the new rules.
“Basically this is going to be self-implementing, and since there’s really only two major app stores, that’s pretty simple,” he said.
Experts said that the bans on providing hosting and other services to WeChat’s American service could quickly disable the app for users in the United States.
Mr. Lewis said that it appeared the app’s payment functions would not work under the rules. Whether users would be able to message other people would hinge on how effectively the administration had been at banning companies from connecting users in the United States with WeChat’s infrastructure in China.
“And it looks to me like they’re certainly trying,” he said.