The owner of TikTok has chosen Oracle over Microsoft as its preferred suitor to buy the popular video-sharing app, according to a source familiar with the deal.

Microsoft announced on Sunday that its bid to buy TikTok had been rejected, removing a leading prospective buyer for the Chinese-owned app a week before President Donald Trump promises to follow through with a plan to ban it in the US.

Microsoft said in a statement TikTok’s parent company Bytedance “let us know today they would not be selling TikTok’s US operations to Microsoft”.

The Trump administration has threatened to ban TikTok by mid-September and ordered ByteDance to sell its US business, claiming national-security risks due to its Chinese ownership.

The government worries about user data being funnelled to Chinese authorities. TikTok denies it is a national-security risk and is suing to stop the administration from the threatened ban.

Walmart had planned to partner with Microsoft on the deal. It is not clear if Walmart is still interested. Oracle has declined to comment.

TikTok also declined to comment on Sunday.

Microsoft said it was “confident our proposal would have been good for TikTok’s users, while protecting national security interests”.

The company said it “would have made significant changes to ensure the service met the highest standards for security, privacy, online safety, and combating disinformation”.