The Supreme Court on Friday upheld a law requiring China's ByteDance to divest its ownership of TikTok by Sunday or face an effective ban on the popular U.S. social video app

ByteDance has so far refused to sell TikTok, meaning many U.S. users could lose access to the app this weekend. The app may still be available for those who already have TikTok installed on their phones, although ByteDance has also threatened to shut down the app.

In a unanimous decision, the Supreme Court sided with the Biden administration, upholding the Apps Protecting Americans from Control by Foreign Adversaries Act signed by President Joe Biden in April.

"There is no question that for more than 170 million Americans, TikTok provides a unique and broad source of expression, participation, and community," the Supreme Court opinion said. "But Congress has determined that divestiture is necessary to address Its national security concerns about TikTok’s data collection practices and relationships with foreign adversaries are well supported.”

Supreme Court Justices Sonia Sotomayor and Neil Gorsuch agreed in writing.

The country's top court said in its opinion that while "data collection and analysis are common practices in this digital age," TikTok's sheer size and its "vulnerability to control by foreign adversaries, as well as the vast amounts of sensitive data collected by the platform," have caused national concern Security concerns.

Under legal terms, third-party Internet service providers such as apple and Google will be punished for supporting TikTok, owned by ByteDance, after the January 19 deadline.

If internet service providers and app store owners comply, they will remove TikTok from their respective app stores, preventing users from downloading TikTok or installing the updates needed to make the app work properly.

White House press secretary Karine Jean-Pierre reiterated President Biden's support for the law in a statement, saying: "TikTok should remain available to Americans, but only owned by the United States or other ownership to address national security concerns determined by Congress in enacting this law.”

"Given the timing, this government recognizes that action to implement this law must be the responsibility of the next government that takes office on Monday," Pierre said.

Kate Ruane, director of the nonprofit Center for Democracy and Technology, criticized the Supreme Court's ruling, saying in a statement that it "undermines the free expression of hundreds of millions of TikTok users in this country and around the world."

“Individuals use the app to create, share information, get news, comment on current issues and promote their businesses — the very expressions the First Amendment is designed to protect,” Ruane said.

TikTok's fate in the United States now lies in the hands of President-elect Donald Trump, who last December asked the Supreme Court to halt the law and give his administration "the opportunity to pursue a political solution to the case." question". "

Trump will be inaugurated on Monday, the day after the TikTok sales deadline. TikTok CEO Shou Chew, one of several tech leaders expected to attend, sat at the podium.

In December, members of the House Select Committee on Chinese Communist Party sent a letter to Apple CEO Tim Cook and Google CEO Sundar Pichai urging executives to start preparing to comply with the law and reminding them that as app store operators responsibilities.

On Friday, the Supreme Court heard oral arguments from lawyers representing TikTok, content creators and the U.S. government. Noel Francisco, TikTok's lead attorney, argued that the law violated the First Amendment rights of the app's 170 million U.S. users. Meanwhile, U.S. Deputy Attorney General Elizabeth Preloga countered that the app's alleged ties to the People's Republic of China through its parent company ByteDance posed a threat to national security.

After the oral arguments, many legal experts believed that the U.S. Supreme Court seemed to be more favorable to the U.S. government’s case involving TikTok’s alleged suspicious relationship with the Chinese government.

Many TikTok creators have been telling their fans to find them on competing social platforms such as Google's YouTube, Meta's Facebook and Instagram, CNBC reported. Separately, CNBC reported that Instagram leaders arranged a meeting after last Friday’s Supreme Court hearing to instruct employees to prepare for a wave of users in court supporting the law.

Chinese social media app and TikTok-like RedNote topped Apple's App Store on Monday, a sign that TikTok's millions of users are looking for alternatives.

The Chinese government is also considering a contingency plan for Elon Musk to acquire TikTok's U.S. operations as part of a number of options aimed at preventing the app from being effectively banned in the U.S., Bloomberg reported on Monday . The plan is one of several the Chinese government is considering as part of larger discussions involving cooperation with the incoming Trump administration, the report said.

watch: Supreme Court hears TikTok ban case.