The bipartisan bill is the latest move in the US against the company and is framed within the context of a trade war between Washington and Beijing.
The proposed legislation would "block and prohibit all transactions" in the US by social media companies with at least one million monthly users that are based in, or under the "substantial influence" of, countries that are considered foreign adversaries, including China, Russia, Iran, North Korea, Cuba and Venezuela.
The bill specifically names TikTok and its parent ByteDance as social media companies for the purposes of the legislation.
The bill was proposed by Senator Marco Rubio, the top Republican on the Senate Intelligence Committee, Republican Congressman Mike Gallagher and Democrat Congresswoman Raja Krishnamoorthi. Last month, Gallagher had indicated their intention to introduce the bill in a Washington Post op-ed.
"The federal government has yet to take a single meaningful action to protect American users from the threat of TikTok," Rubio said in a statement. "There is no more time to waste on meaningless negotiations with a CCP-puppet company. It is time to ban Beijing-controlled TikTok for good."
The move responds to rising concerns voiced by organisations such as the FBI regarding China's potential access to the data generated by the social media app. Since then, several states have taken the step to ban TikTok from government devices.
In the past two weeks, at least seven states have introduced such measures, including Maryland, South Dakota and Utah. The US military, the State Department and the Department of Homeland Security have also restricted TikTok from devices under their control.
"TikTok is a Trojan Horse for the Chinese Communist Party. It's a major security risk to the United States, and until it is forced to sever ties with China completely, it has no place on government devices," senator Josh Hawley has said in a statement.
TikTok, which has more than 100 million users in the US, called the measure a "politically-motivated ban that will do nothing to advance the national security of the United States".
"It's troubling that rather than encouraging the Administration to conclude its national security review of TikTok, some members of Congress have decided to push for a politically motivated ban that will do nothing to advance the national security of the United States," Hilary McQuaide, a spokesperson for TikTok, said in a statement.
"We will continue to brief members of Congress on the plans that have been developed under the oversight of our country's top national security agencies – plans that we are well underway in implementing – to further secure our platform in the United States."
The company added that it was developing plans to further secure the platform in the US as part of the national security review that began under former President Donald Trump.
The legislator's announcement coincides with the publications of the conclusions of the investigation carried out by the Center for Countering Digital Hate (CCDH) into the TikTok algorithm.
The organisations' findings showed that some young TikTok users are being shown potentially dangerous content which could encourage eating disorders, self-harm and suicide, minutes after joining the platform.
The group created two accounts in each of the US, UK, Australia and Canada posing as 13-year-olds. One account in each country was given a female name and the other was given a similar name but with a reference to losing weight included in the username. The content served to both accounts in their first 30 minutes on TikTok was then compared.
The CCDH said one of its accounts was served content referencing suicide within three minutes of joining TikTok and eating disorder content was served to one account within eight minutes.
On average, its accounts were served videos about mental health and body image every 39 seconds.
"Parents will be shocked to learn the truth and will be furious that lawmakers are failing to protect young people from big tech billionaires, their unaccountable social media apps and increasingly aggressive algorithms," said Imran Ahmed, chief executive of the CCDH.
In response to the research, a TikTok spokesperson said: "This activity and resulting experience does not reflect genuine behaviour or viewing experiences of real people.
"We regularly consult with health experts, remove violations of our policies, and provide access to supportive resources for anyone in need.
"We're mindful that triggering content is unique to each individual and remain focused on fostering a safe and comfortable space for everyone, including people who choose to share their recovery journeys or educate others on these important topics."
TikTok has previously faced an effective ban in the US, following an executive order by former President Trump barring new downloads in 2022. However, judges blocked the measure and it was eventually revoked by President Joe Biden.
That same year, the Committee on Foreign Investment in the US – charged with reviewing foreign ownership in the country – also ordered ByteDance to sell TikTok. Negotiations on this issue are still ongoing.
Calls to ban TikTok have also surfaced in countries such as Australia, while Taiwan recently moved to ban it from public devices. India blocked it in 2020 amid a military dispute.
In September, the UK Information Commissioner's Office issued the social media company with a notice of intent – a legal document that precedes a potential fine – over a possible breach of UK data-protection law by failing to protect children's privacy when using the platform.
