TikTok is resuming services to its 170 million users in US after President-elect Donald Trump said he would give the app a reprieve when he takes office on Monday.

On Sunday the Chinese-owned app stopped working for American users, following concerns that their data could be accessed by Chinese officials.

In a statement, TikTok later said it was in the process of “restoring service” just hours after going dark in America.

It thanked the president-elect for “providing the necessary clarity and assurance” and said they would work with Trump “on a long-term solution that keeps TikTok in the United States”.

Posting on Truth Social, a social media platform he owns, Trump said on Sunday: “I’m asking companies not to let TikTok stay dark! I will issue an executive order on Monday to extend the period of time before the law’s prohibitions take effect, so that we can make a deal to protect our national security.”

TikTok’s parent company, Bytedance, previously ignored a law requiring it to sell its US operations to avoid a ban. The law was upheld by Supreme Court on Friday and went into effect on Sunday.

The platform is wildly popular among its many millions of US users. It has also proved a valuable tool for American political campaigns to reach younger voters.

Trump previously backed a TikTok ban, but has more recently professed a “warm spot” for the app, touting the billions of views he says his videos attracted on the platform during last year’s presidential campaign.

Under the law passed last April, the US version of the app would be removed from app stores and web-hosting services.

TikTok has argued that the law violates free speech protections for its users in the country.