The image was shared with his 713K followers and later deleted
Zack Polanski will face no further action after he reposted a photo of a man wearing a T-shirt that called for the decapitation of Nigel Farage.
The image, shared with his 713K followers and later deleted, featured a man wearing a T-shirt that read: "We're only making plans for Nigel," alongside a guillotine.
The Reform UK leader reported Mr Polanski to the police for "incitement to murder" after he shared the post.
Officers said they reviewed the reports after receiving a report on Monday evening.
However, the police have confirmed that no further action will be taken in relation to sharing the image online.
They confirmed that a crime should be recorded in relation to the wearing of the T-shirt, referencing the man in the photo.
The Met Police has transferred the case to Avon and Somerset Police, where the event took place.
A Met Police spokesman said: "We absolutely understand the reaction to this image being shared online, particularly in the context of increasing threats towards politicians.
"We take the safety and security of those in public life, including politicians, very seriously. Where we identify threats we take appropriate action and where there is evidence of offences we will investigate.
“While there will be people who will argue that those who shared the image in this Instagram post should be subject to criminal action, our review has concluded that on this occasion, the threshold is not met.
"We have spoken with those impacted to explain that decision making and to provide reassurance around our ongoing commitment to their security and the additional support available.”
Police also pointed to several reasons for the investigation into Mr Polanski being dropped, including the steps to remove the post from his account when the issue was raised.
They also pointed to the image being 18 in a post containing 20 images, the Green Party statement issued on his behalf, and that Mr Polanski was unaware of the specific image.
The post has since been shared, whether by collaboration, reposting or sharing, by around 130 accounts, the force said, highlighting that individuals should not be treated differently solely because of their public profile.
It is unlikely their actions would have ultimately constituted an offence, police said.
Shortly after the post was uploaded, Mr Farage took to social media to issue a response, writing on X: "This is what Zack Polanski has just posted on his Instagram. If I was to post anything as inciteful then I would expect to be arrested, and so should Polanski."
Zia Yusuf, Reform UK's Home Affairs spokesman, echoed the call for police to look into the post, adding: "Zack Polanski has posted to his 713k Instagram followers a photo of a man in a T-shirt calling for the beheading of Nigel Farage."
"To do this just 2 weeks after our friend Ann was murdered is staggering. Polanski is inciting murder. It must be treated as such by the police."
A Green spokesman said: "After attending a public event, Zack accepted a request to collaborate on a post with several images. Once this image was brought to his attention he immediately unshared the post. He unequivocally does not support this type of dangerous message."
