The US 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 US 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 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."

A TikTok spokesman said the company was "pleased with today's Supreme Court order."

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

It marks a reversal from his first term, when the Republican leader tried to ban the app over security concerns. (AFP)