Martin Lewis has called on the government to make an urgent "intervention" amid the escalating energy bill crisis.
The consumer champion issued the desperate plea to Chancellor Rishi Sunak ahead of an expected 50% hike in the energy price cap.
He warned the impact of the hike will be "hideous and devastating" saying it will cause "real problems" and that "help has to come" with average energy bills set to increase from around £1,275 to £2,000.
He said: "We have at least a year of extremely high prices, which is why it is incredibly important we see a form of intervention coming."
Britons will learn the scale of the financial pain they face when Ofgem makes the announcement at around 11am on Thursday - an hour before the Bank of England is expected to increase interest rates again to tame surging inflation.
The cap, which comes into effect in April, covers consumers on standard variable energy tariffs, rather than fixed tariffs, equating to around 22 million households.
It follows a period of surging wholesale energy costs driven by multiple factors including higher-than-usual demand for gas and lower-than-expected supplies from Russia.
In September, consumer champion Lewis told Yahoo News UK that a "political solution" must be found to address the looming energy crisis - warning millions of Brits will be faced with a choice of "heating or eating".
On Wednesday, Lewis said the next 24 hours will now be pivotal in the crisis, and that he hopes the Chancellor will intervene to help those most in need.
"It is a very big day for energy as to exactly what will happen," he told Yahoo News. "I don't know - but we will hear the price cut rates coming and then, on the back of it, I hope we'll hear mitigation methods - because, bloody hell, do we need them."
Watch: Martin Lewis struggles to help caller with her energy bill
Lewis believes that Sunak is likely to make a two-pronged attack that will see him help the most vulnerable on one hand while also supporting the politically important "squeezed middle" and "Red Wall" seats that drove the Conservatives to election victory in 2019.
"My hope," said Lewis."My hope is that it is big enough to help people. Help has to come. A 50% rise is absolutely unsustainable.
"If I were chancellor, I would probably focus first on: how do I help the people who are at risk of having to either freeze or starve? How do we give them enough money to make sure that isn't going to happen?"
On Wednesday, the Times reported that ministers are planning to back loans of around £6 billion to energy companies.
The companies would then pass on this money to households, saving them around £200 off their energy bills each, in a rebate.
This would come alongside more targeted help, such as an expansion of the Warm Home Discount Scheme.
Lewis lamented there was nothing left in the cupboard to help Brits struggling to pay their energy bills.
"There are very few tools left in my arsenal; you can no longer switch, you're stuck with it."
He also cautioned that energy bills could increase in October when the price cap is reviewed again.
"The worst thing is that if wholesale rates stay where they currently are right now, that won't be the end of it - we expect to see the first October's price cap to rise again by 20%."
Lewis' comments come amid the looming cost-of-living crisis, with experts warning 2022 is set to become "the year of the squeeze" for millions of Brits, leaving them facing a "catastrophic" financial situation.
Earlier this month, the director of the Institute for Fiscal Studies warned that 2022 could be worse than the 2008/09 financial crisis amid soaring inflation and planned hikes in National Insurance contributions in April.
Watch: Cost of living: Households facing 'fuel stress' set to triple as energy bills surge, think-tank warns