The Duke of Sussex has warned AI is learning “how to enter our relationships” as he quipped it had sabotaged his speech when he faced a technical glitch.

Harry had to cut short his impassioned address to the Clinton Global Initiative in New York on Wednesday when the teleprompter failed.

But he was welcomed back to the stage some 40 minutes later to deliver the end of his talk, with the duke saying: “Hello again. So AI got into my speech, so I was asked to come out and finish it.

“Interesting to see what it was so concerned about in part two.”

Harry, who had travelled back to the US for his first public appearance Stateside since returning to live in the UK, urged the world not to wait and see before protecting children from online harm, saying he was speaking “as a father”.

“Innovation has never required us to gamble with our children’s lives. We should not accept that bargain now,” he said.

The duke, father to Prince Archie and Princess Lilibet who are settling into their new schools in the UK, added: “I come to this as a father — one who has shared countless conversations with other parents as they mourned the loss of their children to recklessly built technology,” he said.

“And as a father, I will remind you of the faces that accompanied me the last time I stood before you. Hundreds have become thousands.”

The duke walked across the stage against a backdrop of lock screen photos of children who took their own lives or suffered serious harm through experiences on social media.

Harry, who took part in the first main stage session of the day called Getting Disruption Right, described how new lawsuits had been filed and settled, alleging that AI companion chatbots had contributed to the deaths of teenagers “who trusted them with things no child should have been left alone to ask an algorithm”.

The duke spoke of a growing threat from AI, saying: “It’s the same playbook that built the last crisis — only now the technology is more persuasive, more intimate, and more powerful.

“And there is another difference this time.

“Social media learned how to capture our attention. AI is learning how to enter our relationships.”

He added: “It doesn’t just want your attention, it wants your attachment. It wants to be the thing you confide in.

“The thing that remembers you. The thing that tells you it understands you. The ultimate sycophant. For a child, that distinction matters enormously.

“We have spent years trying to loosen technology’s grip on children’s attention. We cannot wait another decade to discover what happens when technology has a grip on their relationships.”

Harry and the Duchess of Sussex’s Archewell foundation launched the Parents Network in 2024 as a support network for parents of children affected by online harm.

He also addressed the rapid development of AI and the concerns raised by those building AI systems.

And he spoke of the progress in American courts against firms such as Meta and moves to ban youngsters’ access to social media, but he added: “Bans, settlements, and payouts are incomplete remedies. Bans do nothing to address dangerous design.”

The duke added: “The good news: we proved pressure works. The bad news: we proved how long we are willing to wait.

“The damage was already done to a generation of children and parents. We do not have years for what comes next.”

He followed this with a long pause, adding: “And that’s it”, hiding his surprise at having to finish his speech early.

A spokesman for the duke confirmed there had been a fault with the teleprompter and it was fixed while others including former US secretary of state Hillary Clinton took to the stage, with Harry returning later to deliver the second part of his address.

The duke made his appearance as his uncle Earl Spencer continued to defend his controversial memoir about Diana, Princess of Wales.

Charles Spencer claims in his book that the King, then the Prince of Wales, said about Diana “we’ll forget her soon enough” during an argument over whether the then-Princes William and Harry should walk behind their mother’s coffin in her funeral procession.

The two-day CGI annual meeting is being hosted by former US president Bill Clinton, Hillary and Chelsea Clinton in a bid to bring together leaders to help solve urgent global issues.