The U.S. Commerce Department may enforce the shutdown on Tik Tok and WeChat which was announced in August and plans to do so by September 20, over the national security concerns.

WeChat will effectively shut down in the US on Sunday, but people will still be able to use TikTok until 12 November, when it could also be completely banned.

TikTok said it was "disappointed" with the order and disagreed with the commerce department, saying it had already committed to "unprecedented levels of additional transparency" in light of the Trump administration's concerns.

"We will continue to challenge the unjust executive order, which was enacted without due process and threatens to deprive the American people and small businesses across the US of a significant platform for both a voice and livelihoods."

Tencent - the owner of WeChat - said the announced restrictions were "unfortunate", but said they would continue talks with the US government "to achieve a long-term solution".

If a planned partnership between US tech firm Oracle and TikTok owner ByteDance is agreed and approved by President Trump, the app will not be banned.

Trump told reporters on Friday he believed there could be a deal on TikTok "quickly", adding that while the US needed "security from China", TikTok was "an amazing company, very popular."

"Maybe we can keep a lot of people happy but have the security that we need," he said.

"At the president's direction, we have taken significant action to combat China's malicious collection of American citizens' personal data," the US Department of Commerce Secretary Wilbur Ross said in a statement.

The department acknowledged that the threats posed by WeChat and TikTok were not identical but said that each collected "vast swathes of data from users, including network activity, location data, and browsing and search histories".

The order means that from Sunday, people will not be able to use WeChat to transfer funds or process payments to or from people in the US.

But TikTok users will still be able to use their app virtually as normal, although they will not be able to download new updates.

"The President has provided until November 12 for the national security concerns posed by TikTok to be resolved," the commerce department said. After this point, some technical transactions will be banned on the app and functionality will be affected.

TikTok's owner, Bytedance, now has to try to find a more palatable deal - and this may be tough. It's been reported that China would rather chose to close down TikTok than be forced to sell to the US.

Friday's statement from the commerce department said the governing Chinese Communist Party "has demonstrated the means and motives to use these apps to threaten the national security, foreign policy, and the economy of the US.

"ByteDance has denied that it holds any user data in China, saying it is stored in the US and in Singapore. Tencent, which owns WeChat, has said that messages on its app are private.

While TikTok has millions of users in the US, it is not clear how many of WeChat's billion users are based outside China, although it is likely to be a significant number.

But the US is not the only country concerned about the companies. India has already banned TikTok and WeChat, while the UK Information Commissioner's Office, a privacy watchdog, is currently investigating TikTok.