Broadcasting watchdog Ofcom has launched an urgent investigation after a TV network showed an interview with David Icke, in which the conspiracy theorist suggested Israel was using the pandemic to "test its technology".
London Live broadcast part of a lengthy interview with the former sports presenter on the first night of Passover last Wednesday.
The channel billed the one-hour and 45-minute programme, hosted by entrepreneur Brian Rose, as "David Icke talks about his theory behind the pandemic, the lockdown and the economic crash".
In a one-minute clip uploaded to Twitter, Mr Icke tried to connect coronavirus research and Israel, while also claiming possible moves to require people to be vaccinated was "fascism".
Mr Icke has previously spoken of "the global conspiracy Rothschild-Zionism, a secret society putting its agents in places of power" – and listed Jewish people he says are part of the plot.
During advert breaks, London Live displayed a notice saying: "The views expressed in this programme are those of the individual articulating them and not necessarily those of London Live."
Culture Secretary Oliver Dowden later called for Ofcom to take "the appropriate action" and accused London Live of allowing Mr Icke to air "lunatic conspiracy theories.".
The regulator Ofcom received more than 40 complaints about Wednesday’s programme and it confirmed it was investigating.
London Live is owned by Russian businessman Evgeny Lebedev, and broadcasts from the same offices as the Evening Standard newspaper and The Independent, which he also owns.
A London Live spokesperson said: "We are aware of the culture secretary's comments, and have proactively contacted Ofcom to offer our co-operation and support as part of their assessment."
An Ofcom spokesperson said: "We have assessed this programme, and we are concerned that it raises potential issues under our rules.
"We are now investigating as a matter of urgency."
The regulator cannot intervene before a programme is screened but can issue fines or more serious sanctions after broadcast.