Elon Musk's artificial intelligence tool Grok has limited its image generation and editing capabilities to paying subscribers following widespread outcry over its use to create sexually explicit and violent imagery without consent.

The move comes after the X platform, owned by Musk, faced threats of regulatory action from the UK government and warnings about criminal imagery of children. The tool had been used to manipulate images of women and children, digitally removing clothing and placing them in sexualised positions.

The Internet Watch Foundation confirmed its analysts had discovered criminal imagery of children aged between 11 and 13 which appeared to have been created using Grok. Hannah Swirsky, head of policy at the charity, said the restriction "does not undo the harm which has been done".

"We do not believe it is good enough to simply limit access to a tool which should never have had the capacity to create the kind of imagery we have seen in recent days," she said.

Prime minister Sir Keir Starmer described the content as "disgraceful" and "disgusting", demanding that X "get a grip" of the situation. He indicated that communications regulator Ofcom had the government's "full support" to take action, including considering a potential ban of X in the UK.

"It's unlawful. We're not going to tolerate it. I've asked for all options to be on the table," Starmer said.

Under the Online Safety Act, Ofcom has the power to seek court orders to block websites or apps in the UK and can impose fines of up to 10 per cent of a company's global turnover.

Research by AI Forensics, a Paris-based non-profit organisation, found approximately 800 images and videos created by the Grok Imagine app containing pornographic and sexually violent content. Paul Bouchaud, a researcher at the organisation, said the material included "fully pornographic videos" that "look professional".

However, Professor Clare McGlynn, an expert in the legal regulation of pornography and online abuse, criticised the response as insufficient. "Instead of taking the responsible steps to ensure Grok could not be used for abusive purposes, it has withdrawn access for the vast majority of users," she said.

The Information Commissioner's Office has contacted X and xAI to seek clarity on measures in place to comply with UK data protection law, stating it will assess whether further action is required.

Anna Turley, chair of the Labour party and a minister in the Cabinet Office, said conversations were ongoing within government and Labour about their continued use of X.

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