Labour will try to shame Tory MPs into backing a windfall tax on oil and gas giants this week to help families struggling in the cost-of-living crisis.
Keir Starmer ’s party plans to expose Conservative splits on Tuesday by forcing a Commons vote on the move it claims would hand the hardest-hit households £600.
Business Secretary Kwasi Kwarteng confirmed Tory MPs would attempt to torpedo the bid.
Demanding a one-off levy on the fossil fuel firms, Shadow Climate Change Secretary Ed Miliband said: “I think it is obscene, frankly, that we have as a result of soaring energy bills, oil and gas companies making billions of pounds in our country, and the Government refuses to put a windfall tax on them.
"It is shameful, it should shame them."
Ministers including Boris Johnson have fuelled confusion about the Government’s position, repeatedly insisting they do not like windfall taxes yet refusing to rule out imposing a one-off levy on the fossil fuel firms.
One-time Labour leader Mr Miiband believed Chancellor Rishi Sunak will eventually have to U-turn and introduce the tax.
“I'm not interested in their internal machinations about this, because every day that goes by when they refuse to do the right thing is another day when millions of people in this country have sleepless nights about how they are going to afford their bills,” he Sky News' Sophy Ridge On Sunday.
"My message to the Chancellor is this - you're going to do a windfall tax.
“I believe he is going to do a windfall tax because, frankly, it's an unanswerable case. Get on with it and do it, and bring real help to families."
The energy price cap rocketed by 54% last month - costing families an extra £693 a year and taking average annual bills to £1,971.
Inflation is running at 7% and is expected to race past 10% later this year.
Trades Union Congress chief Frances O’Grady backed the call for a windfall tax and demanded an emergency Budget to help families battling the cost-of-living crisis.
She said: “What we need is for the Chancellor, who I'm afraid woefully failed working families, to come back with that windfall tax on energy companies that would provide some immediate relief."
But Business Secretary Kwasi Kwarteng again renewed his opposition to the plan.
Asked if the Government would support Labour’s bid, he insisted: “Of course not.”
He told BBC1’s Sunday Morning show: "I don't believe in windfall taxes because what you are taxing is investment in jobs, you are taxing investment in wealth creation, you're taxing investment in new technologies such as hydrogen and carbon capture.
"We want to see more investment. We don't want to see taxes which essentially act against any incentive to invest."
Quizzed about splits between him and Mr Sunak, who has kept open the option of a windfall tax, Mr Kwarteng told Sky News’ Sophy Ridge on Sunday programme: “I’ve always argued against it publicly and privately.
“But as every Chancellor I can remember has said, four months before the budget, no option is off the table.
“It is entirely reasonable.”
