Britain’s plans to ban social media for under-16s will push teenagers towards more harmful platforms, the world’s biggest technology companies have said as ministers push to enact the new restrictions by next spring.

Meta, YouTube and Snapchat have all criticised the ban, which was announced by Keir Starmer on Monday and would stop younger teenagers from using their services, The Guardian reported.

A spokesperson for Meta, which owns Facebook and Instagram, said, “As we’ve seen in Australia, bans risk isolating teens from online communities and information, and driving them to unregulated alternatives that lack built-in protections and parental controls.”

YouTube said in a statement, “Blanket bans push kids out of such curated, supervised, beneficial experiences and towards anonymous, less-safe services.”

Snapchat said, “Because the majority of time spent on Snapchat is in private messaging between friends and family, an outright ban that disconnects teens from those relationships doesn’t make them safer – it may simply push them to less safe platforms.”

Starmer announced the ban at a Downing Street press conference, despite having previously been sceptical about the idea. Allies say that if he is ousted as prime minister in the coming weeks this will form part of his political legacy.

He said, “Social media is making children unhappy, it’s making it easier for bullies to harass and abuse them, and it could even be harming their mental health.”

He argued the ban was not anti-tech. “I do not accept, and I will never accept, that you can’t be both pro tech and AI, and at the same time say we must protect our children.”

The plan, which goes further than the one enacted earlier this year in Australia, includes a ban on all the main social media platforms, with separate restrictions on online products such as gaming apps, including removing the option to chat to strangers.

Under-16s will be prevented from downloading Snapchat, TikTok, YouTube, Instagram, Facebook and X, and from livestreaming themselves. Under-18s will be stopped from using romantic chatbots designed to simulate sexual relationships.

“This is not something I do lightly, and I will not present it as cost-free, as if social media has [brought no] benefits to young people, because clearly that is wrong,” Starmer said. “But government is always about choices, and it’s clear to me that a total ban is the right choice.”

He said predictions that many teenagers would circumvent the ban, as in Australia, was not the point.

“We don’t say: ‘Oh, look, a teenager managed to get a drink somehow, so let’s not bother banning alcohol sales for children.’ We don’t do that, do we?

 “I just don’t accept that. Our laws are rules, but they’re also an expression of our values. They shape the social contract, and so this will change the conversations that parents have, and the expectations of children over time.

“It will make a huge difference. It will make our children safer. It will make our children happier. It will give them more time, more security, full freedom to grow up, more opportunity, and that, at the end of the day, is what this government is about.”

The announcement was welcomed by campaigners, many of whom are bereaved parents who say social media played a role in their children’s deaths.

Esther Ghey, the mother of the murdered teenager Brianna Ghey, said she was happy about the ban, saying it would “potentially save so many children’s lives”.

Starmer made the announcement in front of an audience that included a number of campaigners for a ban, including parents who had lost children, whom he thanked.

He said: “I am not prepared to compromise on the safety and happiness of our children, and that is why this ban must happen, and that is why this ban will happen.

“Yes, it’s hard – hard to legislate for, hard to regulate, hard to enforce. That’s why we sought a wide range of views on this. That’s why we listened to people, had a conversation, we looked carefully at the evidence, learned from countries like Australia that are taking similar steps.”

The government said on Sunday that nine in 10 parents backed a minimum age of 16 for accessing the apps in responses supplied to its “growing up in the online world” consultation.