President Donald Trump has voiced approval of Oracle Corp's reported bid for TikTok, the Chinese video-sharing sensation that could also be bought by Microsoft.

Reports said Oracle -- whose chairman Larry Ellison has raised millions in campaign funds for Trump -- was weighing a bid for TikTok's operations in the US, Canada, Australia and New Zealand.

The Trump administration has given TikTok's parent company ByteDance a 90-day deadline to divest the app before it is banned in the United States, citing national security concerns.

Taking questions after a speech on Tuesday in Yuma, Arizona, Trump said: "I think Oracle is a great company, and I think its owner is a tremendous guy. He’s a tremendous person.

"I think that Oracle would be certainly somebody that could handle it."

The president said the eventual buyer would have to "make sure the United States is well compensated."

According to the Wall Street Journal, Ellison held a Trump fundraiser at his California home in February, raising $7 million.

Trump's action against TikTok came after he claimed China could use it to track the locations of federal employees, build dossiers on people for blackmail, and conduct corporate espionage.

In an online post this week, the company said: "TikTok has never provided any US user data to the Chinese government, nor would it do so if asked."

China on Monday slammed Washington for using "digital gunboat diplomacy" in the TikTok case.

Chinese foreign ministry spokesman Zhao Lijian said TikTok had done everything required by the US, including hiring Americans as its top executives, hosting its servers in the US and making public its source code.