Google and Apple must be ready to remove TikTok from its US app stores by January, lawmakers said in a letter to the companies' CEOs on Friday, according to media reports.

The video sharing app has millions of users worldwide, but has faced questions over the security of data and links to the government in Beijing.

The bipartisan letter came from two leaders of the US House of Representatives’ committee on China: Republican Representative John Moolenaar, who is the committee’s chair, and the group’s top Democrat Representative Raja Krishnamoorthi.

The letter comes after a US appeals court rejected an emergency bid by TikTok to temporarily block a law that could ban the app completely by next month.

The ruling means TikTok must move quickly with an urgent request to the Supreme Court to block or overturn a law that would require its Chinese parent, ByteDance to divest TikTok in the US by January 19 or face a ban on the app.

The social media company (TikTok and ByteDance) lost its appeal against the law in a decision handed down on Friday and said it would appeal to the Supreme Court. 

The companies had warned that the law would “shut down TikTok- one of the nation’s most popular speech platforms - for its more than 170 million domestic monthly users”.

The law was passed after the US government raised concerns of the apps links to the Chinese state.

Under the new law, the US government will also have the power to ban other foreign-owned apps that could raise concerns about the collection of Americans’ data. 

President-elected, Donald Trump had vowed to prevent the ban on TikTok after he unsuccessfully tried to ban the social media app during his first term in 2020.