Mr Trump signed an executive order last week ordering sweeping but vague bans on dealings with the Chinese owners of TikTok and the messaging app WeChat, saying they are a threat to national security, foreign policy and the economy
His new order said there is “credible evidence that leads me to believe that ByteDance … might take action that threatens to impair the national security of the United States”.
It remains unclear what the TikTok orders mean for the app’s 100 million users in the US, many of them teenagers or young adults who use it to post and watch short form videos.
Mr Trump has also ordered ByteDance to divest itself of “any data obtained or derived” from TikTok users in the US.
Microsoft is in talks to buy parts of the Chinese company.
White House press secretary Kayleigh McEnany defended Mr Trump’s earlier TikTok and WeChat orders, telling reporters he was exercising his emergency authority under a 1977 law enabling the president to regulate international commerce to address unusual threats.
She said: “The administration is committed to protecting the American people from all cyber threats and these apps collect significant amounts of private data on users.”
TikTok said it spent nearly a year trying to engage in “good faith” with the US government to address these concerns.
The company said: “What we encountered instead was that the Administration paid no attention to facts, dictated terms of an agreement without going through standard legal processes, and tried to insert itself into negotiations between private businesses.”