The US House of Representatives has approved a landmark bill that could see TikTok banned in America.
The measure gives the social media giant's parent company, ByteDance, six months to sell its controlling stake, or the app will be banned in the US.
While the House bill passed by 352-65 in a bipartisan vote, it faces uncertain prospects in the US Senate.
Lawmakers have long held concerns about China's influence over TikTok, which which has over 150 million US users.
ByteDance is based in Beijing and is subject to a national security law requiring it to share data with Chinese officials.
Mike Gallagher, a Wisconsin Republican who co-authored the bill, said the US could not "take the risk of having a dominant news platform in America controlled or owned by a company that is beholden to the Chinese Communist Party".
TikTok has tried to reassure regulators that it has taken steps to ensure US user data has been walled off from ByteDance employees in China.
However, an investigation from the Wall Street Journal in January found the system was still "porous", with data being unofficially shared between TikTok in the US and ByteDance in China. High-profile cases, including one incident where ByteDance employees in China accessed a journalist's data to track down their sources, have stoked concerns.
Speaking ahead of the vote, Hakeem Jeffries - the top Democrat in the House - welcomed the bill, saying it would decrease "the likelihood that TikTok user data is exploited and privacy undermined by a hostile foreign adversary".
Senate Majority Leader Chuck Schumer said the chamber would review the legislation.
Its prospects in the upper chamber of Congress are unclear in the wake of Republican presidential candidate Donald Trump speaking out against the proposed TikTok ban.
The former president, who tried to ban the app during his term in office, changed his position after a recent meeting with Republican donor Jeff Yass, who owns a major stake in ByteDance.
Mr Trump's opposition was echoed by some House members on Wednesday.
Georgia congresswoman Marjorie Taylor Greene wrote on social media that the bill could allow Congress to force the sale of other corporations by claiming to be protecting US data from foreign adversaries.
Some Democrats are also opposed to a ban, fearing it could alienate the app's youthful userbase as the party struggles to retain its hold over younger voters.
But the leaders of the Senate intelligence committee welcomed the House vote. Mark Warner, a Democrat, and Marco Rubio, a Republican, said they were determined to shepherd the bill through the chamber.
"We are united in our concern about the national security threat posed by TikTok - a platform with enormous power to influence and divide Americans whose parent company ByteDance remains legally required to do the bidding of the Chinese Communist Party," they said in a statement.
After the vote, TikTok appeared to renew its push to have users lobby Congress, sending another notification to users urging them to contact their representatives. A similar move last week saw congressional offices bombarded with calls, a move that some staffers told the BBC had hardened opposition to the company.
If the bill does manage to secure approval in the Senate, President Joe Biden has promised to sign it as soon as it lands on his desk, potentially kicking off a new diplomatic spat with China.
ByteDance would have to seek approval from Chinese officials to complete a forced divestiture. Beijing has vowed to oppose any forced sale. Foreign ministry spokesperson Wang Wenbin said on Wednesday that the move would "come back to bite the US".
"Although the United States has never found evidence that TikTok threatens US national security, it has not stopped suppressing TikTok," he told reporters.
"This kind of bullying behaviour that cannot win in fair competition disrupts companies' normal business activity, damages the confidence of international investors in the investment environment, and damages the normal international economic and trade order."
Even if ByteDance does secure approval to sell its stake in TikTok, it is unclear whether any of its competitors have the funding to launch a bid for the platform. The company has previously valued the app at around $268bn. The price tag could scare off some investors.
But analysts told the BBC there would plenty of potentially interested buyers in the US - especially from the tech worlds. What deal might ultimately pass muster is another question, given the cost and anti-monopoly concerns weighing on the tech sector.
"All the big social media companies would be interested but I think they would face a lot of anti-trust hurdles… There are other firms in the social media space that are smaller like Snapchat that would be interested but wouldn't be able to afford it," Emarketer analyst Jasmine Enberg told the BBC.
When the Trump administration ordered a sale in 2020, some of the biggest firms in the US emerged to explore bids, which then reportedly valued the firm at about $50bn.
Microsoft ultimately lost out to a team that included Walmart and software giant Oracle, led by Larry Ellison and Safra Catz, who had ties with the Trump administration. The deal fell apart amid legal challenges and the change-over to a new administration.
Today, TikTok's reach and advertising revenue have increased significantly. Research firm Emarketer estimates TikTok will bring in about $8.66bn in ad revenue from the US this year, compared with less than $1bn in 2020.
BBC