Washington DC - The Supreme Court agreed on Wednesday to hear TikTok's appeal of a law that would force its Chinese owner to sell the online video-sharing platform or shut it down.

The top court scheduled oral arguments in the case for January 10, nine days before TikTok faces a ban unless ByteDance divests from the popular app.

The law, signed by President Joe Biden in April, would block TikTok from US app stores and web hosting services unless ByteDance sells its stake by January 19.

TikTok is arguing that the law, the Protecting Americans from Foreign Adversary Controlled Applications Act, violates its First Amendment free speech rights.

"Congress has enacted a massive and unprecedented speech restriction," TikTok, which claims to have more than 170 million monthly US users, said in a filing with the Supreme Court.

Should the law take effect, it would "shutter one of America's most popular speech platforms the day before a presidential inauguration," TikTok said.

"This, in turn, will silence the speech of Applicants and the many Americans who use the platform to communicate about politics, commerce, arts, and other matters of public concern," it added.

"Applicants – as well as countless small businesses who rely on the platform – also will suffer substantial and unrecoverable monetary and competitive harms."

The potential ban could strain US-China relations just as Donald Trump prepares to take office as president on January 20.

At a press conference on Monday, Trump said he has "a warm spot" for TikTok and that his administration would take a look at the app and the potential ban.

Trump has emerged as an unlikely TikTok ally amid concerns that a ban on the app would mainly benefit Meta, the Facebook parent company owned by Mark Zuckerberg.

Trump's stance reflects conservative criticism of Meta for allegedly suppressing right-wing content, including the former president himself being banned from Facebook after the January 6, 2021, Capitol riot by his supporters.

Trump's support for TikTok marks a reversal from his first term, when the Republican leader tried to ban the app over similar security concerns.

The US government alleges TikTok allows Beijing to collect data and spy on users. It also says the video hosting service is a conduit to spread propaganda, though China and ByteDance strongly deny these claims.

A three-judge US appeals court panel earlier this month unanimously upheld the law's premise that TikTok divesting from Chinese ownership "is essential to protect our national security."