Nigel Farage has demanded an immediate general election, claiming Andy Burnham has no mandate to run the country.
The Reform UK leader said his party could produce a "historic upset", but Mr Farage warned that if he fails to enter No 10, Britain risks "turning into a third world country" within 10 years.
He added that "nothing will get better under Andy Burnham", who will become prime minister on Monday after being confirmed as the new leader of the Labour Party.
Mr Farage, who is fighting a by-election in Clacton after resigning as an MP in protest at parliamentary and media scrutiny of his finances, said: “The only certainty with Burnham is we’re going to get more of the same, but they’ll go further to the left than they already are.”
“He (Burnham) says he wants to have the biggest change of direction in politics in 40 years, outside of 25,000 voters in Makerfield he has literally no mandate for this at all,” Mr Farage added.
Mr Burnham has said he will stick to Labour’s 2024 manifesto commitment not to increase income tax, national insurance or VAT.
But in a speech to the CPAC GB conference in London, Mr Farage said: “Taxes are going to rise and there’s talk, of course, of property taxes, which will collapse the housing market, especially in London and the South East, but it’ll do great damage elsewhere in the country.
“Top rate tax, I’ve no doubt, will go up and all of these things are happening for a man that has no mandate whatsoever.
“On immigration, he’s never shown the slightest concern about what’s going on and of course, do we think Andy Burnham will take us out of the ECHR (European Convention on Human Rights), so we’re back fully in control of our borders? Not a hope in hell.”
The Reform leader said there “must be an immediate general election so the country can decide the future”.
Mr Farage said Reform UK was well-placed to win the “battle for the soul of our nation”.
“We managed to raise more money last year than any other political party and we are genuinely doing everything we can to get ready to fight that next general election, whenever it begins, and to win it,” he said.
“And I believe we can win it. I believe an historic upset is on the cards.
“I believe the British people have simply had enough of weak, gutless, spineless leadership that cares more about opinion in the international community than it cares about the collective good of the people living in this country.”
Mr Farage claimed that if Reform failed to win the next election, the UK would “go bust” and “I honestly believe we’re less than a decade away from effectively turning into a third world country, and I will be damned if I’m going to see that”.
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