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 declined to comment. 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.
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.
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.