Meta has agreed to pay $US23 billion ($23.6 billion) and add child-safety measures to its Facebook and Instagram platforms to end a landmark trial over teen social media addiction and settle claims filed by 47 US states, state attorneys-general have announced.

The lawsuit accused Meta of contributing to the youth mental health crisis by deliberately designing features that addict children to its platforms and hiding them from the public. The head of Instagram, began his testimony late on Tuesday, local time, and defended Meta’s record and progress on child safety and privacy.

Under the proposed settlement, Meta agreed to adopt a series of safety features, including a “hard cap” on daily time limits and pauses for children using Instagram and Facebook. It will eliminate push notifications during weekday school hours and bring in “robust” age assurance measures and “age-appropriate” content controls to prevent bullying and harmful material about eating disorders and self-harm. There will also be stronger and more user-friendly parental controls and limits on social comparison features such as “like” counts.

The deal cuts short a trial that was expected to see chief executive Mark Zuckerberg take the stand in California, one of the 29 states to sue the tech giant. The agreement is worth $US353 million in Virginia alone and is one of the biggest in state consumer protection history, Attorney-General Jones said in a statement.

The settlement “will put an end to these dangerous practices and deliver meaningful relief that will protect children from online harm”. After reaching the settlement, Meta framed the deal as a template for the rest of the industry and pressed its competitors to match it.

New Zealand prime minister Luxon has said his party will introduce a bill in parliament that ⁠seeks to ban children ⁠under ​16 from using social media, proposing fines of up to 10% of a platform’s global revenue for non-compliance.

The bill would ⁠require social media platforms to take reasonable steps to verify users’ ages, including by utilising existing account information, facial technology and ⁠digital identity documents. Luxon explained that this decision is to protect children from harm that may be caused by harmful content, addictive technology and pressures they are not ‌equipped to deal with.

In December, Australia became the world’s first country to ban social media for children under 16, blocking them from platforms including TikTok, Alphabet’s YouTube and Meta’s Instagram ⁠and Facebook.

That legislation had been a “colossal failure”, New Zealand’s foreign minister Peters said, adding that ​keeping children off ​social media should be the responsibility ​of parents.

Canada Prime Minister Carney defended the French influence of Canada on Monday while American negotiators saw the French language in Canada as an “irritant”, days after receiving widespread praise from political leaders for rejecting a US trade proposal that many perceived as weakening the country’s Francophone culture.

The prime minister’s remarks came hours after US president Trump showed little interest in retreating from the spat, posting on social media that Canada had been “ripping off the United States of America for years” and threatening a swath of new, economically devastating tariffs on cars and trucks.

Quebec, Canada’s predominantly French-speaking province, has long sought to protect its distinct identity, at times with laws that clashed with the federal government and the Canadian charter of rights and freedoms. In recent years those rules have also frustrated US negotiators, who have framed them as trade irritants. Bill 96, for example, requires products sold in Quebec to have a French description and for trademarks using generic terms to be translated into French, while Bill 109 compels media services such as Netflix, Spotify and Apple to promote and prioritize French content for Quebec users.

Quebec’s premier, Christine Fréchette, said Carney had made the right decision in walking away from talks that looked to cross a “red line” for Francophones.

Carney’s decision to abandon trade talks with the US spurred declarations from political leaders and pundits in Canada that the country is now fully locked into an economic war with its longtime ally.