A US judge early on Sunday blocked the Donald Trump administration from requiring Apple Inc and Alphabet Inc’s Google to remove Chinese-owned WeChat for downloads by late Sunday.

US Magistrate Judge Laurel Beeler in San Francisco said WeChat users who filed a lawsuit “have shown serious questions going to the merits of the First Amendment claim, the balance of hardships tips in the plaintiff’s favour”.

Her 22-page order added the prohibitions “burden substantially more speech than is necessary to serve the government’s significant interest in national security, especially given the lack of substitute channels for communication”.

On Friday, the US commerce department had issued an order citing national security to block the app from US app stores owned by Tencent Holdings and the justice department had urged Beeler not to block the order. Tencent and the justice department did not immediately comment.

Beeler’s preliminary injunction also blocked the commerce order that would have barred other transactions with WeChat in the US that could have dramatically degraded the site’s usability for current US users or potentially made it unusable. The US commerce department did not immediately comment.

WeChat has had an average of 19 million daily active users in the US, analytics firms Apptopia said in early August. It is popular among Chinese students, Americans living in China and some Americans who have personal or business relationships in China.

The justice department said blocking the order would “frustrate and displace the President’s determination of how best to address threats to national security”.

Beeler wrote “certainly the government’s overarching national-security interest is significant. But on this record — while the government has established that China’s activities raise significant national security concerns — it has put in little evidence that its effective ban of WeChat for all US users addresses those concerns”.

WeChat is an all-in-one mobile app that combines services similar to Facebook, WhatsApp, Instagram and Venmo. The app is an essential part of daily life for many in China and boasts more than 1 billion users. The justice department also argued that WeChat users could switch to other apps or platforms.

The WeChat Users Alliance praised the ruling “as an important and hard-fought victory” for “millions of WeChat users in the US”.

Michael Bien, a lawyer for the users, said “the United States has never shut down a major platform for communications, not even during war times. There are serious First Amendment problems with the WeChat ban, which targets the Chinese American community”.

He added the order “trampled on their First Amendment guaranteed freedoms to speak, to worship, to read and react to the press, and to organise and associate for numerous purposes”. Beeler also noted “there are obvious alternatives to a complete ban, such as barring WeChat from government devices”.