Nigel Farage has compared Reform UK's rise in the polls, with Donald Trump's recent election victory in the US.
At a rally held in Tory leader Kemi Badenoch's constituency, four of Reform's five MPs gave speeches.
During the North West Essex rally, Mr Farage told Reform members the Conservative Party "should be bloody scared of you".
Recent polling has suggested the party has pulled level with, and possibly overtaken, the Tories.
A Techne UK poll put Reform in second place with 24%, one point ahead of the Conservatives on 23% and two points behind first-placed Labour on 26%.
Mr Farage said: "I think also we're beginning to see a wave that is crossing the Atlantic from the east coast of America, where Donald Trump, standing on a platform many of whose policies were not dissimilar to what we put to the British people in that contract last July, has won this incredible victory and got off to the most amazing start.
"And even those people that don't like him say, you know what? He gets things done.
"People look at us and say 'like Trump these people will get things done', and believe me, we will.
"This is not just going to be an earthquake in British politics. This is going to be the biggest historical political change this country has ever seen."
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In advance of the various claims put forward by Mr Farage, Ms Badenoch dismissed Reform UK as a "protest party".
She told reporters she was not worried by its presence in her political back garden, adding that talking about Labour's farming policy was "much more important than having a rally about myself".
During a visit to a farm in Cheshire, Ms Badenoch said it was "not a surprise" that Reform UK was gaining in the poll as a "protest party".
It came after a row between the Tory leader and Mr Farage over party membership numbers during the Christmas period.
(c) Sky News 2025: Nigel Farage compares Reform polling with Donald Trump election victory
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