A group of WeChat users asked a federal judge to block the Trump administration from imposing a ban on using the messaging app in the US.

In a lawsuit filed in federal court in San Francisco on Aug. 21, Chinese-American lawyers who formed the WeChat User Coalition in the US allege President Donald Trump's ban.

According to the decree on August 6, Trump banned all individuals and organizations in the US from conducting transactions with WeChat and TikTok from mid-September to "protect national security".

The lawyers also said that the decree was related to Trump's criticisms of China in recent months, including blaming Beijing for the Covid-19 pandemic.

"Neither the decree nor the White House provides concrete evidence to support the argument that using WeChat in the US harms national security," the lawsuit said.

They also allege Trump's decree violates WeChat users' freedom of expression as well as their procedural rights by not announcing specific prohibited behavior.

Representatives from the US Department of Justice have not yet responded to the lawsuit.

WeChat, owned by Tencent Group, is used by millions in the US to communicate with people whose native language is Chinese, according to the alliance.

The Trump administration contends that Chinese businesses pose a serious threat, despite Beijing's denial.

US companies with operations in China expressed concern about the WeChat ban because the app is an indispensable tool for doing business in the country.

According to some sources familiar with the matter, the Trump administration is looking to reassure American companies, including Apple, that they can still do business with the WeChat messaging app in China.

According to Reuters, TikTok will also file a lawsuit against the Trump administration over an ordinance banning transactions with US companies.