US District Judge Robert Pitman granted a preliminary injunction against the Texas App Store Accountability Act just days before it was set to take effect on January 1, calling the law too far-reaching and vaguely written.

The preliminary injunction blocks the Texas law's enforcement while the case proceeds through federal court.

The ruling came as governments increasingly grapple with regulating children's online activity amid growing concerns about social media addiction and exposure to inappropriate content.

The law was to be the first of several in the United States to come into force, with Congress also considering a nationwide version, though furious lobbying against such measures by Apple and others has blocked the measure for now.

Australia this month imposed a social media ban for users under 16 for apps like Facebook, TikTok and X, opting for a different route instead of putting the responsibility on app stores for age verification.

The Texas law would have required Apple or Google's app stores to verify users' ages before allowing downloads and mandated that minors obtain parental permission for each app download or in-app purchase.

Violations would have carried fines up to $10,000.

"The Act is akin to a law that would require every bookstore to verify the age of every customer at the door and, for minors, require parental consent before the child or teen could enter and again when they try to purchase a book," Pitman wrote in his 20-page ruling.

The Computer & Communications Industry Association (CCIA), whose members include Google, Apple and Amazon, challenged the law arguing it would restrict access to a vast range of protected speech including news apps, educational content and health applications.

Pitman acknowledged legitimate concerns about children's wellbeing online, noting social media's potential mental health impacts.

However, he ruled Texas failed to prove the broad restrictions were the least invasive way to protect minors, suggesting alternatives like voluntary content filters or targeted regulations for apps with proven addictive qualities.

"No doubt a State possesses legitimate power to protect children from harm, but that does not include a free-floating power to restrict the ideas to which children may be exposed," Pitman wrote.