A judge has blocked a US government attempt to ban the Chinese messaging and payments app, WeChat.
US Magistrate Judge Laurel Beeler said the ban raised serious questions related to the constitution's first amendment, guaranteeing free speech.
The Department of Commerce had announced a bar on WeChat appearing in US app stores from Sunday, effectively shutting it down.
The Trump administration has alleged it threatens national security.
It says it could pass user data to the Chinese government.
Both WeChat and China have strongly denied the claim. Tencent, the conglomerate that owns WeChat, had previously described the US ban as "unfortunate".
The ruling comes just after TikTok, which was also named in the Department of Commerce order, reached a deal with US firms Oracle and Walmart to hopefully allow them to keep operating.
What happened in court?
The Justice Department asked for the order not to be blocked after a group of WeChat users filed a lawsuit challenging it.
The department argued it would "frustrate and displace the president's determination of how best to address threats to national security".
However Judge Beeler, sitting in San Francisco, noted that "while the general evidence about the threat to national security related to China (regarding technology and mobile technology) is considerable, the specific evidence about WeChat is modest".
Why does the US want the apps banned?
The US Department of Commerce Secretary Wilbur Ross said in a statement that the decision to block the app was taken "to combat China's malicious collection of American citizens' personal data".
The department said WeChat collected "vast swathes of data from users, including network activity, location data, and browsing and search histories".
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 Read More – Source