Domestic energy users whose households have a low income are spending double as much of their budget on heating their homes as those from higher-income backgrounds.
This is the finding of research carried out by the Institute of Fiscal Studies.
William Baker, fuel poverty expert at Consumer Focus, commented that this means low-income households could be forced to choose between eating and heating in the coldest months or face "unmanageable" levels of debt.
He said: "Inflation rates for fuel are already higher than for other goods, and double digit price increases will push millions more on low incomes into fuel poverty."
The lobby group has called on energy suppliers to introduce cheap energy deals which do not rely on paying by debit card or are only available online.
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