Secretary of State Mike Pompeo has said the US is "looking at" banning Chinese social media apps, including TikTok, over allegations Beijing is using them to spy on users.
India has already barred the wildly popular TikTok app over national security and privacy concerns while other countries are reportedly mulling similar measures.
Asked on Monday by Fox News's Laura Ingraham if the US should consider blocking the apps - "especially Tik Tok" - the country's top diplomat said the Trump administration was "taking this very seriously; we are certainly looking at it."
Mr Pompeo said the US had been working for a "long time" on the "problems" of Chinese technology in infrastructure and was "making real progress."
Mike Pompeo at the 2020 Munich Security Conference. Source: Getty
"With respect to Chinese apps on people's cell phones, I can assure you the United States will get this one right too," he said.
"I don't want to get out in front of the president, but it's something we are looking at."
It comes as TikTok said it will exit the Hong Kong market following China's establishment of a sweeping new national security law for the semi-autonomous city.
"In light of recent events, we've decided to stop operations of the TikTok app in Hong Kong," a TikTok spokesman said late on Monday in response to a Reuters question about its commitment to the market.
Mr Pompeo earlier lashed out at what he called China's "Orwellian" moves to censor activists, schools and libraries in Hong Kong under the new law.
Authorities in the financial hub have ordered schools to remove books for review under the law, which has criminalised certain opinions such as calls for independence or more autonomy.
Riot police officers arrest a protester in Hong Kong. Source: Getty
Libraries in Hong Kong said they were pulling titles written by a handful of pro-democracy activists.
"The Chinese Communist Party's destruction of free Hong Kong continues," Mr Pompeo said in a sharply worded statement.
"With the ink barely dry on the repressive National Security Law, local authorities - in an Orwellian move - have now established a central government national security office, started removing books critical of the CCP from library shelves, banned political slogans, and are now requiring schools to enforce censorship," he said.
Mr Pompeo condemned what he called the "latest assaults on the rights and freedoms of the people of Hong Kong."
"Until now, Hong Kong flourished because it allowed free thinking and free speech, under an independent rule of law. No more," he said.
Beijing has faced a groundswell of criticism from primarily Western nations over its decision to impose the security law, which outlaws acts of subversion, secession, terrorism and colluding with foreign forces.
US Vice President Mike Pence told CNBC last week that the law was a "betrayal" and "unacceptable to freedom-loving people around the world."
Last week the US Congress passed tough new sanctions targeting banks involved in violating Hong Kong's autonomy.
The act would punish banks - including by blocking loans from US institutions - if they conduct "significant transactions" with officials who violate the city's autonomy.
President Donald Trump must sign the legislation for it to take effect.
