(Reuters) - TikTok remained unavailable on Apple ( AAPL ) and Google app stores in the U.S. on Tuesday, a day after President Donald Trump signed an executive order delaying the enforcement of a ban on the popular Chinese-owned short-video app by 75 days.

The order came amid growing doubts on the future of the app that went dark on Saturday, shortly before a law that cited national security to say the Chinese owner ByteDance should sell it or face a ban in the U.S. came into effect on Sunday.

Although TikTok resumed service after Trump's assurances that the company and its partners would not face hefty fines to keep the app running, it was yet to return to the app stores.

The delay, analysts doubted, could be because Google and Apple ( AAPL ) are awaiting additional protections before bypassing the ban that punishes the companies for hosting or distributing the app.

Apple's ( AAPL ) App Store said, "TikTok and other ByteDance apps are not available in the country or region you're in", while Google Play said, "Downloads for this app are paused due to current US legal requirements".

Google, Apple ( AAPL ) and TikTok did not respond to requests for comment.

Bill Ford, CEO of TikTok investor General Atlantic, told CNBC on Tuesday there are ways to change TikTok U.S. ownership, that do not necessarily involve its sale.

"I don't think that necessarily has to mean a divestiture," he said, referring to the law that bans TikTok, adding that 60% of TikTok's parent company, ByteDance, was controlled by non- Chinese shareholders.

ByteDance is nearly 60% owned by institutional investors such as BlackRock and General Atlantic, while its founders and employees own 20% each.

(Reporting by Jaspreet Singh in Bengaluru; Editing by Arun Koyyur)