Mr Farage has previously told Sky News this was “not on my agenda” but did not categorically reject the idea when pressed repeatedly.
Speaking today to Sky News’ political editor Beth Rigby, he said the party he currently leads is “a new political movement” and “I want nothing to do with them [the Conservatives]”.
Asked if that means he is ruling out joining, he said: “If you don’t work out that’s a yes, I don’t know what else I’ve got to say.”
Mr Farage has weaponised the Tory implosion and his primary argument at this election is that the Conservative Party is spent and needs replacing.
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He wants his party to become the official opposition to an expected Labour government and ruled out any sort of electoral pact with the Tories, having agreed to one in 2019 to help Boris Johnson win seats.
Back then Reform UK was known as the Brexit Party – but Mr Farage says the Tories’ failure to cut immigration since leaving the EU has betrayed voters.
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“They have no interest in the truth. For them, it’s all a game,” he told Beth Rigby.
“They’re awful, they are ghastly,” he added.
Mr Farage’s language goes further than an interview two weeks ago when he was also asked about joining the Tories.
He is making his eighth bid to become an MP, this time in Clacton in Essex, and while some polls project him to win, the UK’s first past-the-post voting system makes it difficult for Reform to make huge strides in a couple of elections.
Earlier this month Sky News’ deputy political editor Sam Coates asked him if the Tory party would be a better vehicle for his ambitions post-election and if he would rule out joining.
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Will Nigel Farage join the Tories?
Mr Farage said he could not see it happening and called the question “moronic”.
Pressed if that was a categorical rejection, he said he had “no intention” of joining the Tories but did not rule it out.
Some Tories want Mr Farage to join the fold to combat the threat of Reform UK, which is to the right of the Conservative Party.
Reform’s popularity in the polls surged after Mr Farage announced he would be taking over as leader and putting himself forward as a candidate in the election.
Former Home Secretary Suella Braverman and former immigration minister Robert Jenrick are in favour of him joining but the issue is divisive – with senior figures like Priti Patel, Kemi Badenoch and James Cleverly being against it.
After enjoying a relatively smooth start to his election campaign, Mr Farage has this week been embroiled in a race row after one of his campaigners was caught on camera using a racial slur to describe the prime minister – and one candidate has now defected to the Tories.