WASHINGTON (Reuters) - The Justice Department late on Wednesday asked a U.S. appeals court to reject an emergency bid by TikTok to temporarily block a law that would require its Chinese parent company ByteDance to divest the short-video app by Jan. 19 or face a ban.

TikTok and ByteDance on Monday filed the emergency motion with the U.S. Court of Appeals for the District of Columbia, warning without court action the law will "shut down TikTok - one of the nation's most popular speech platforms - for its more than 170 million domestic monthly users."

The Justice Department said the court should not delay the law's effective date arguing "continued Chinese control of the TikTok application poses a continuing threat to national security."

(Reporting by David Shepardson; Editing by Muralikumar Anantharaman)