App will become unavailable in US on 19 January, unless Trump directs justice department not to enforce the law

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The US supreme court has issued a ruling upholding a nationwide ban on TikTok unless it sells to an owner in the US. The nine justices voted unanimously in a decision on Friday that sides with the majority of the US Congress and the US Department of Justice that the hugely popular social media app is a threat to US national security.

“We conclude that the challenged provisions do not violate petitioners’ First Amendment rights,” the justices wrote. “The judgment of the United States court of appeals for the District of Columbia Circuit is affirmed.” In December, a Washington DC appeals court upheld the ban.