Elon Musk-owned social network X on Friday accused Britain's government of "overreach" with a new law designed to protect children from harmful online content such as pornography.
The Online Safety Act's "laudable intentions are at risk of being overshadowed by the breadth of its regulatory reach," X said in a post to its Global Government Affairs account.
"A plan ostensibly intended to keep children safe is at risk of seriously infringing on the public's right to free expression," it added, arguing that the impact "shows what happens when oversight becomes overreach".
Beyond the law, X criticised a separate new code of conduct for online platforms as "parallel and duplicative" as well questioning the free-speech impact of a new police unit tasked with monitoring social media.
The social network nevertheless last week introduced formal systems for age verification in response to the British law as well as new rules in Ireland and the wider European Union.
Its options range from estimating the age of a user based on the date their account was created or their email address, to requesting a selfie whose age would be determined by artificial intelligence, or uploading an official ID document.
Media regulator Ofcom says such age checks -- required since July 25 -- must be "technically accurate, robust, reliable and fair".
Platforms failing to comply risk fines of up to 18 million pounds ($24 million) or 10 percent of their global revenue -- whichever is larger.
Serious infringers could be blocked from British territory.
The fight over age verification to access sensitive content in Britain echoes months of debate in France over new rules requiring pornography sites to verify users' ages -- a step also required by many US states.
While hailed by child safety campaigners, opponents say such requirements risk compromising legitimate users' privacy -- or even exposing them to scams such as identity theft if the personal details used to verify their age were to be hacked.
Many people resort to virtual private networks (VPNs) to get around territorial restrictions on access to online content.
The most popular free apps on Apple's UK download store since last week have been VPNs, with one, Proton, reporting earlier this week a 1,800 percent rise in downloads, according to British media.
