Starmer’s office welcomed the investigation, saying that Ofcom “has our full support to take any action it sees fit”.
Ofcom said it had contacted X on January 5 asking it to explain the steps it has taken to protect UK users.
Without sharing details of the exchange, the regulator said that X responded within the given timeframe.
The formal investigation will determine whether X “failed to comply with its legal obligations”.
Contacted by AFP, X referred to a previous statement, which said: “We take action against illegal content on X ... by removing it, permanently suspending accounts, and working with local governments and law enforcement as necessary.”
Global backlash
Under Britain’s Online Safety Act, which entered force in July, websites, social media and video-sharing platforms hosting potentially harmful content are required to implement strict age verification through tools such as facial imagery or credit card checks.
It is meanwhile illegal for media sites to create or share non-consensual intimate images, or child sexual abuse material, including sexual deepfakes created with AI.
Ofcom has the power to impose fines of 10% of worldwide revenue for breaches of these rules.
Addressing Parliament, Technology Minister Liz Kendall pledged to go further, by creating a new criminal offence which would “make it illegal for companies to supply tools designed to create non-consensual internet images”.
She added that “tackling violence against women and girls is as important online as it is in the real world”.
Grok appeared to deflect the international criticism with a new monetisation policy at the end of last week, posting on X that the tool was now “limited to paying subscribers”, alongside a link to a premium subscription.
Starmer condemned the move as an affront to victims and “not a solution”.
Musk brushed off the UK’s criticism this weekend, posting on X that “they just want to suppress free speech”.
On Saturday, Indonesia became the first country to deny all access to the tool, with Malaysia following suit on Sunday.
The European Commission, which acts as the EU’s digital watchdog, has ordered X to retain all internal documents and data related to Grok until the end of 2026 in response to the uproar.
“We will not be outsourcing child protection and consent to Silicon Valley,” European Commission head Ursula von der Leyen said on Monday.
“If they don’t act, we will.”
- Agence France-Presse