"Frankly, we have no choice. We have to save it," Trump said at a rally on Sunday (Jan. 19) ahead of his inauguration, adding that the United States would seek a joint venture to revive the short-video sharing app used by 170 million Americans.

“Thanks to the efforts of President-elect Donald Trump, TikTok is back in the United States,” TikTok said in a message to users hours before the rally.

TikTok also issued a statement after US users said they were able to access the Chinese-owned service's website, while the much more widely used TikTok app itself has begun to come back online for some users with some basic services. However, as of Sunday evening, the platform was still unavailable for download on US app stores.

"As agreed with service providers, TikTok is in the process of restoring service," TikTok said, thanking President-elect Donald Trump for "providing much-needed clarity and assurance to service providers that they will not be subject to any penalties (for) providing TikTok to more than 170 million Americans and allowing more than 7 million small businesses to thrive."

TikTok’s public thanks to Mr Trump, a day before he takes office, come at a tense time in US-China relations. Mr Trump has said he intends to impose tariffs on China but has also said there will be more direct communication with the Chinese leader.

The Chinese Embassy in Washington on Friday accused the United States of unfairly using state power to suppress TikTok. “China will take all necessary measures to resolutely safeguard its legitimate rights and interests,” a spokesperson said.

TikTok was shut down for US users late Saturday, ahead of a law that shuts down the app on national security grounds that took effect Sunday. US officials have warned that Americans’ data is at risk of being misused, according to its Chinese parent company ByteDance.

Mr Trump said he would "extend the time before the ban goes into effect, so we can reach an agreement that protects our national security".

"I want the United States to own 50% of a joint venture," Trump wrote on the social network Truth Social.

Previously, Mr. Trump said he might delay the TikTok ban for 90 days after taking office, a promise that TikTok cited in a notice sent to users on the app.

In August 2020, Mr. Trump signed an executive order giving ByteDance 90 days to sell TikTok but later approved a deal as a partnership rather than a divestiture that would include Oracle and Walmart taking stakes in the new company.

Not everyone in Trump’s Republican Party agrees with the effort to circumvent the law and “save TikTok.” Republican senators Tom Cotton and Pete Ricketts said: “Now that the law is in effect, there is no legal basis for any kind of ‘extension’ of the law’s effective date. For TikTok to operate again in the future, ByteDance must agree to a sale that meets the law’s qualified divestment requirements by severing all ties between TikTok and China.”