Can Trump save TikTok from a potential ban?

The answer to whether President-elect Donald J. Trump can — or will — save TikTok from an impending ban is unclear.

Mr. Trump, who takes office the day after the Chinese-owned app is scheduled to be banned on Sunday, has previously promised to spare the social media platform. He is also considered an executive order aimed at allowing TikTok to continue operating in the United States.

But on Friday, the president-elect took a non-committal tone on his own social media platform, Truth Social.

“The Supreme Court’s decision was expected and everyone must respect it,” wrote Mr. Trump. “My decision on TikTok will be made in the not too distant future, but I need time to review the situation. Stay tuned!”

The law upheld by the Supreme Court requires TikTok’s Chinese parent company, ByteDance, to sell the app or face a ban. As part of that, app stores like Apple and Google are required to stop offering TikTok for downloads. The law also prohibits cloud computing companies from operating the app.

It is unclear whether an order from Mr. Trump could effectively stop that kind of ban. Legal experts said he could direct the Justice Department not to enforce the law or delay enforcement for a specified period, but it was uncertain how such an order would fare if challenged in court.

“You could have a policy of not enforcing this ban,” said Ryan Calo, a professor at the University of Washington School of Law who was part of a group of legal scholars urging the Supreme Court to overturn the TikTok ban.

That maneuver would be complicated by the fact that Mr. Trump had to convince Apple, Google and other companies that work with TikTok that there was no risk that they would be punished for violating a law that was already on the books.

The law also allows the president to extend the deadline for a sale only if there is “significant progress” toward a deal that would put TikTok in the hands of a non-Chinese owner, which also requires that the deal be possible to complete before for the 90-day length of the extension. It is unclear exactly how that extension would work if Mr. Trump tried to implement it after the ban had already gone into effect.

TikTok maintained throughout its legal challenge to the law that such a sale was impossible in part because of the time frame set out in the law. A group led by Frank McCourt, a billionaire who made his money in real estate, has made a bid to buy the app in recent months.

Mr. Trump has a third option: appealing to Congress to overturn a law that received largely bipartisan approval just last year.