The government will consult on whether social media should be banned for under-16s in the UK.
It said "immediate action" would give Ofsted the power to check policies on phone use when it inspects schools, and it expected schools to be "phone-free by default" as a result of the announcement.
A similar ban took effect in Australia in December 2025, the first of its kind in the world. Other countries are said to be considering such a law.
It comes after more than 60 Labour MPs wrote to the prime minister about the issue, with the mother of murdered teenager Brianna Ghey also calling on the government to act.
"Some argue that vulnerable children need access to social media to find their community," Brianna's mother Esther Ghey wrote in a letter seen by the BBC.
