Zack Polanski has refused three times to apologise to Nigel Farage for re-posting a photo of a man wearing a t-shirt with an image of a guillotine and the slogan “we’re only making plans for Nigel”.

Reform UK’s home affairs spokesperson, Zia Yusuf, said the image showed a “photo of man calling for the beheading of Nigel Farage”, which he said could be an “incitement to murder”.

The Green Party of England and Wales leader was reported to the Met over the photo, which he then deleted, but told the BBC he had not been contacted by police.

Speaking to BBC Newsnight, he said he would not apologise for an “inadvertent mistake” that he said Farage had amplified in a “fundamentally dishonest way”.

The row kicked off on Monday evening when Polanski shared the photo, which he said was the fifth image in a series of 20 from a party, having accepted a request to collaborate with the Instagram account of a photographer at the event.

Posting a screenshot on X, Reform UK leader Farage said: “If I was to post anything as inciteful then I would expect to be arrested, and so should Polanski.”

Asked if he wanted to apologise to Farage, Polanski said: “Well, if I’d done it deliberately I’d be apologising but because this was a mistake I think the important thing is that I point out this was a mistake, that I also make sure that I condemn political violence, and also crucially I make a commitment to be better on social media.”

Asked for a second time whether he would apologise, Polanski refused because he said Farage had cropped the image to make it look like he had posted it himself, which he said was “fundamentally dishonest” and only amplified the problem.

Saying he had received a death threat earlier on Tuesday, Polanski added: “The ramping up of the language to say ‘this is incitement to murder me’ feels like that’s also putting me in a dangerous spot.”

Given a third chance to apologise, Polanski doubled down and said: “You know as well as I do that as soon as I do that Nigel Farage would run all over social media saying he was correct about incitement to murder and this would all ramp up again.

“I think it’s important that I draw a line and don’t play his game… It is important that he’s kept safe, it is important we condemn political violence, but I also recognise this as the political attack that it is.”

“If Nigel Farage wants to apologise for all the times that he’s put other people in danger then I will be happy to make an apology,” Polanski added.

The Green leader explained he had not read the slogan on the T-shirt when he accepted the collaboration because “what I was seeing was people partying” and he only noticed the man was wearing a rainbow hat as he flicked through.

“It feels quite surreal to be having this conversation,” he said, adding: “I think it would be odd for the police to speak to me about that because I think it’s quite obvious I’ve not done anything wrong other than make an inadvertent mistake.”

The Metropolitan Police said there was no update on the complaint they had received on Monday.

On Tuesday, Reform asked the monitoring officer from the Greater London Authority, where Polanski is an elected member, to investigate whether he had breached the code of conduct.

Keith Prince, a Reform London Assembly Member, said: “To say that he was unaware of what he was promoting is frankly risible.”

A Reform UK source told BBC Newsnight: “It’s truly astonishing and quite frankly sickening that Zack Polanski won’t apologise for inciting murder.

“He admits it was wrong. He admits it’s dangerous, but he still refuses to apologise. Mr Polanski is not fit to lead a national political party.”

Asked about the row on Tuesday, Work and Pensions Secretary Pat McFadden said there was a “duty on all politicians to be careful about what they post”, especially in light of the death of former MP Ann Widdecombe earlier this month.

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