A top White House official said he expected President Trump to act firmly against the TikTok and WeChat social media apps, prompting an angry response from China on Monday.
Trump last week had said he is considering banning the wildly popular TikTok app as a way to punish China over the coronavirus pandemic.
China dismissed White House trade advisor Peter Navarro's comments as "ridiculous and narrow-minded", and slammed the United States as "the world's real hacker empire" amid rising tensions between the two superpowers.
"For a long time now, it (the US) has carried out indiscriminate and illegal cyber attacks, surveillance and theft of secrets on a global scale," said Chinese foreign ministry spokeswoman Hua Chunying at a routine briefing.
"The US continues to have strong values, but why is it so scared of a fun video-sharing social media network loved by young people?"
In an interview with Fox News on Sunday, Navarro argued that "what the American people have to understand is all of the data that goes into those mobile apps that kids have so much fun with... goes right to servers in China, right to the Chinese military, the Chinese Communist Party."
He said these apps can be used to steal intellectual property. "So expect strong actions on that" by Trump, Navarro warned.
ByteDance and China
TikTok belongs to the Chinese group ByteDance and has nearly one billion users worldwide.
It has sought to distance itself from its Chinese owners, pointing out it has an American CEO and consistently denying allegations that it shares data with Beijing.
WeChat, owned by Tencent, is a versatile app with more than one billion users in China who use it for text messaging, mobile payments and social media.
Navarro also accused TikTok's new boss Kevin Mayer, former head of Disney's streaming platforms, of being a puppet.
On Friday, Amazon said it mistakenly sent workers an email telling them to dump the TikTok mobile application from their cell phones because of security concerns.
An Amazon spokesperson later told AFP "there is no change to our policies right now with regard to
The research firm eMarketer estimates TikTok has more than 52 million US users, having gained about 12 million since the outbreak of the coronavirus pandemic. TikTok is especially popular with young smartphone users.