Australia has become the first country in the world to introduce a social media ban for children and young people under the age of 16.
They are no longer allowed to have their own accounts on major social media platforms including Instagram, TikTok, Snapchat, Facebook, Reddit and YouTube.
"This is indeed a proud day to be Australian," Prime Minister Anthony Albanese told reporters on Wednesday.
"It is one of the biggest social and cultural changes that our nation has faced," he said, adding that the law would help give children a normal childhood, provide parents with peace of mind and serve as an example for other countries.
Affected companies had a year to introduce age verification measures, and violations will result in heavy fines. Messaging services such as WhatsApp, emails, online games and educational offerings are exempt.
Albanese's government wants to protect young people from risks such as cyberbullying, problematic consumption and distressing content with the law that came into force on Wednesday.
Critics claim that the ban is disproportionate, and a legal challenge to it has already been filed with the Supreme Court. Many are convinced that teenagers will simply switch to other services, where risks and checks are even more difficult to monitor.
"It won't be perfect. This is a big change," Albanese said. "Success is the fact that it's happening. Success is the fact that we're having this discussion."
According to Australian media reports, social media platform Reddit is preparing to challenge the ban in court. The company had earlier said it would comply with the rules despite disagreeing with the terms of the law.
Other countries are considering following Australia's lead. In November, Denmark announced an agreement to restrict children under 15 from using certain social media platforms over concerns about youth mental health.
In September, European Commission President Ursula von der Leyen said she was "inspired" by Australia's "common sense" move to introduce age restrictions.
