WeChat, the Chinese messaging app that was set to get effectively switched off for American users Sunday night, for now will still be available and operational in the U.S.

A federal judge in San Francisco issued a ruling early Sunday issuing a preliminary injunction blocking the Trump administration’s order to ban the WeChat app, which is owned by China internet giant Tencent.

Magistrate Judge Laurel Beeler, of the U.S. District Court for the District of Northern California, said in her ruling that the plaintiffs in the case successfully argued the merits of their claim that the Commerce Department’s Sept. 18 order — forcing Apple and Google to remove WeChat as of Sunday night — violates their First Amendment rights.

The WeChat users who filed the request for an emergency injunction “have shown serious questions going to the merits of the First Amendment claim,” Beeler said in the decision, and therefore “the balance of hardships tips in the plaintiffs’ favor.”

The Trump administration has cited national-security concerns, postulating that Chinese government agents could demand access to data from WeChat on U.S. users. Beeler wrote 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.”

Beeler added that the U.S. government had other options at its disposal to achieve its stated national security objectives, such as banning WeChat from use on government devices, which is a step that Australia has taken.

Meanwhile, with respect to TikTok, the Commerce Department late Saturday deferred the Sept. 20 ban on downloads of the social video app until next Sunday, Sept. 27, citing President Trump’s provisional approval of ByteDance’s deal to sell majority control of TikTok to U.S.-based owners including Oracle and Walmart.

The WeChat case was brought by American users of the app who are not affiliated with the Chinese company. At a court conference in the WeChat case Friday, Serena Orloff, an attorney for the U.S. Justice Department, argued that the order does not violate the First Amendment because WeChat users can switch to other messaging apps like Facebook’s Messenger or Line. Attorney Michael Bien, representing the plaintiffs, disputed that argument. “That is a deprivation of their fundamental rights,” he said. “It’s a prior restraint.”

Tencent declined to comment on the Sunday ruling.

The Commerce Department rule would have prohibited the provision of service “to distribute or maintain the WeChat or TikTok mobile applications, constituent code, or application updates through an online mobile application store in the U.S.” as of Sept. 20.

Specifically relating to WeChat, as of Sunday, the now-stayed order prohibits “any provision of services through the WeChat mobile application for the purpose of transferring funds or processing payments within the U.S.”

The ACLU last week blasted the Trump app bans as abridging First Amendment rights of U.S. users. “Millions of people in the United States watch or post videos to TikTok and rely on WeChat for connections to family, friends, and work relationships. They are all engaging in First Amendment-protected speech, association, and expression,” the civil-rights advocacy organization said in a blog post.

In the U.S., WeChat is far smaller than TikTok. For the week ended Aug. 15, TikTok had 52.1 million weekly active users in the U.S., according to analytics firm App Annie. By comparison, WeChat had 3.3 million monthly active users in August, per App Annie.