By David Shepardson

WASHINGTON (Reuters) - TikTok and parent company ByteDance face a key court hearing on Monday in a legal battle seeking to block a law that could ban the app used by 170 million Americans as soon as Jan. 19.

The U.S. Court of Appeals for the District of Columbia will hold oral arguments on the legal challenge, putting the fate of Chinese-owned TikTok in the middle of the final weeks of the 2024 presidential election.

Both Republican presidential candidate Donald Trump and Vice President Kamala Harris are active on TikTok seeking to court younger voters.

TikTok and ByteDance argue the law is unconstitutional and violates Americans' free speech rights saying it is "a radical departure from this country's tradition of championing an open Internet."