Sir Ed Davey is calling on the UK’s communications regulator Ofcom to “go after” Elon Musk over “crimes” he claims are being committed on the tech mogul’s social media platform X.

The Liberal Democrat leader said Musk should be held personally accountable for breaches of the Online Safety Act, which the billionaire has said is putting free speech at risk.

In an interview with the BBC’s Laura Kuenssberg, Davey claimed X had shown “adverts for people who want to show videos with paedophile images, self-harming, grooming”.

He called on Ofcom to launch an investigation into Musk and X, as his party gathered in Bournemouth for its annual conference. X has been contacted for a response.

Under the Online Safety Act, which came into force earlier this year, internet companies have been forced to introduce stricter age verification checks and face big fines for failing to remove illegal content.

The government insists the laws, passed by the previous Conservative government but brought into effect by Labour, will protect children.

But it has faced a backlash from US tech giants, with Elon Musk saying last month that its real purpose was “suppression of the people” and that Ofcom had taken a “heavy-handed approach” to enforcement.

But Sir Ed claimed Musk “had taken away the child safety team” at X, allowing harmful and illegal content on to the platorm.

“He [Musk} is actually, I think, committing crimes,” he told Laura Kuenssberg.

“Ofcom should go after him. The laws are there. What his business is doing is against the law because it is disgusting.”

Sir Ed has already clashed with Musk over his criticism of the tech mogul’s appearance, via video link, at last weekend’s United the Kingdom rally in London.

Addressing the rally organised by far-right activist Tommy Robinson, Musk criticised “uncontrolled migration” and said: “Whether you choose violence or not, violence is coming to you. You either fight back or you die.”

Sir Ed accused Musk of “inciting violence” and called on him to face sanctions, prompting the X and Tesla owner to brand him a “craven coward”.

The Lib Dem leader plans to use his keynote speech at his party’s conference on Tuesday to step up his criticism of Musk, accusing him of meddling in British democracy.

“It’s not because he cares about the British people, and our rights and our freedoms. It’s all about his ego, power and wealth,” Sir Ed will say.

“He rails against the Online Safety Act, but not because he cares about free speech.

“Like so many on the far-right – or the far-left – Elon Musk doesn’t really believe in free speech. He just believes in free speech for people who agree with him.

“It’s because he wants to carry on running his social media platform without taking any responsibility for the terrible harm it is causing – especially to our children.”

The Lib Dems also plan to table a motion when Parliament returns summoning Musk to appear before MPs to be held to account for his actions at the Unite the Kingdom rally.

They will attempt to activate a little-used Parliamentary device to summon Musk to the bar of the House of Commons to be reprimanded by MPs.

Watch the full interview with Sir Ed Davey on Sunday with Laura Kuenssberg at 0900 BST and on BBC Iplayer