The criticism follows Newark and Nottinghamshire Agricultural Society's decision to host the vegan event on its grounds for the next three years.
Chief Executive of The Countryside Alliance, Tim Bonner, who claims its members are 'coming under increasing attack from vegan activists', has urged the Society to cancel the event to 'protect the farming community'.
'Aggressive anti-farming agenda'
Bonner told The Telegraph: "It's quite extraordinary that a Society with the charitable object of promoting agriculture should be hosting an event that has at its core an aggressive anti-farming agenda.
"The Society's showground, which was created to promote farming in Nottinghamshire, is now being used as a training ground for extremists who campaign against livestock farming and the rural way of life.
"It's difficult to understand why the Society is determined to carry on hosting this event when presented with unarguable evidence that it involves the spreading of an aggressive anti-farming agenda."
Bonner added: "Animal rights extremists from all over the world will be gathering to share tactics and train activists."
'Veganism requires both farming and agriculture'
According to The Telegraph, a spokesperson for Vegan Camp Out - which attracted around 5,000 people from more than 30 countries last year - said: "[The festival] is a family-friendly event that promotes a lifestyle centered around compassion. The event includes fitness workshops, live music, delicious food, and talks from a variety of people.
"The Camp-Out does not promote, engage in or otherwise encourage violent behavior or illegal activity. [Its] organizers are not opposed to agriculture or farming as a whole, as veganism requires both farming and agriculture to produce amazing plant-based food."
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