Los Angeles, California - TikTok restored service in the US Sunday after briefly going dark thanks to a dramatic last-minute intervention by President-elect Donald Trump, who promised to delay a ban on the app.

The company credited Trump, who retakes power on Monday, for making the reversal possible.

TikTok had gone dark in the US late Saturday as a deadline for its Chinese owners ByteDance to sell its US subsidiary to non-Chinese buyers loomed.

Earlier Sunday, as millions of dismayed users found themselves barred from the app, Trump promised to issue an executive order delaying the ban to allow time to "make a deal."

He also called in a post on his Truth Social platform for the US to take partial ownership of TikTok.

In a statement posted on X following Trump's comments, TikTok said it "is in the process of restoring service."

"We thank President Trump for providing the necessary clarity and assurance to our service providers that they will face no penalties providing TikTok to over 170 million Americans."

There was no mention of Trump's call for part American ownership of the app.

The law passed by Congress allows for a 90-day delay of the ban if the White House can show progress toward a viable deal, but so far, ByteDance has flatly refused any sale.

The Biden administration said it would leave enforcement of the law to Trump.

A last-minute proposal made Saturday by the highly valued start-up Perplexity AI offered a merger with the US subsidiary of TikTok, a source with knowledge of the deal told AFP.

Frank McCourt, the former Los Angeles Dodgers owner, has also made an offer to purchase TikTok's US activities.