US President-elect Donald Trump has said he would "most likely" give TikTok a 90-day reprieve from a potential ban in the United States after he takes office on Monday.
His comments came after the Supreme Court upheld a law banning TikTok in the United States on national security grounds if its Chinese parent company ByteDance does not sell it, putting the popular short-video app on track to go dark in just two days.
"The 90-day extension is something that will be most likely done, because it's appropriate," he told NBC in an interview.
"If I decide to do that, I'll probably announce it on Monday," he added.
The court's 9-0 decision throws the social media platform - and its 170 million American users - into limbo, and its fate in the hands of Mr Trump.
Mr Trump, who in 2020 had tried to ban TikTok, has previously said he plans to take action to save the app.
TikTok CEO Shou Zi Chew plans to attend Mr Trump's second inauguration in Washington.
Mr Trump said he and Chinese President Xi Jinping discussed TikTok in a phone call.
Meanwhile TikTok warned it will go dark in the United States unless President Joe Biden's administration provides assurances to companies like Apple and Google that it will not face enforcement actions when a ban takes effect.
"Unless the Biden Administration immediately provides a definitive statement to satisfy the most critical service providers ensuring non-enforcement, unfortunately TikTok will be forced to go dark on 19 January," the company said.
The White House declined to comment.
Apple, Alphabet's Google, Oracle and others could face massive fines if they continue to provide services to TikTok after the ban takes effect.
The law was passed by an overwhelming bipartisan majority in Congress last year and signed by Mr Biden, though a growing chorus of politicians who voted for it are now seeking to keep TikTok operating in the United States.
Read more: Joe Biden or Donald Trump can still rescue TikTok - here's how
TikTok, ByteDance and some of the app's users challenged the law, but the Supreme Court decided that it did not violate the US Constitution's First Amendment protection against government abridgment of free speech as they had argued.
ByteDance has done little to divest of TikTok by the deadline set under the law.
'Foreign adversary control'
For years TikTok's Chinese ownership has raised concerns among US leaders, and the TikTok fight has unfolded at a time of rising trade tensions between the world's two biggest economies.
Politicians and Mr Biden's administration have said China could use TikTok to amass data on millions of Americans for harassment, recruitment and espionage.
"TikTok's scale and susceptibility to foreign adversary control, together with the vast swaths of sensitive data the platform collects, justify differential treatment to address the government's national security concerns," the Supreme Court said in the unsigned opinion.
TikTok has become one of the most prominent social media platforms in the US, particularly among young people who use it for short-form videos, including many who use it as a platform for small businesses.
The company's powerful algorithm, its main asset, feeds individual users short videos tailored to their liking. The platform presents a vast collection of user-submitted videos that can be viewed with a smartphone app or on the internet.
Attorney General Merrick Garland said in a statement the ruling affirmed that the law protects US national security.
"Authoritarian regimes should not have unfettered access to millions of Americans' sensitive data," Mr Garland added.
What happens next
The Biden administration has emphasised that TikTok could continue operating if it is freed from China's control. The White House said that Mr Biden will not take any action to save TikTok.
Mr Biden has not formally invoked a 90-day delay in the deadline as allowed by the law.
"This decision is going to be made by the next president anyway," Mr Biden told reporters.
White House Press Secretary Karine Jean-Pierre said actions to implement the law "must fall to the next administration" while the Justice Department said "implementing and ensuring compliance with the law after it goes into effect on 19 January - will be a process that plays out over time".
TikTok said those statements "have failed to provide the necessary clarity and assurance to the service providers that are integral to maintaining TikTok's availability to over 170 million Americans".
A viable buyer could still emerge, or Mr Trump could invoke a law called the International Emergency Economic Powers Act, stating that keeping TikTok is beneficial for national security.
Only one notable bidder has emerged so far - Frank McCourt, former owner of the Los Angeles Dodgers baseball team, who said he believes TikTok is worth about $20 billion without its algorithm.
