Dec 18 (Reuters) - The U.S. Supreme Court decided on

Wednesday to hear a bid by TikTok and its China-based parent

company ByteDance to block a law intended to force the sale of

the short-video app by Jan. 19 or face a ban on national

security grounds.

The justices did not immediately act on an emergency request

by TikTok and ByteDance, as well as some of its users who post

content on the social media platform, for an injunction to halt

the looming ban, opting instead to hear arguments on the matter

on Jan. 10.

The challengers are appealing a lower court's ruling that

upheld the law. TikTok is used by about 170 million Americans.