Europe's energy bills are set to increase next year, according to the Russian gas giant Gazprom, which supplies a quarter of the continent's gas.
Gas bills could climb by up to 15 per cent, the price comparison service SimplySwitch.com has forecast.
Any rise in the price of gas will also mean that the UK's electricity prices will rise as well, SimplySwitch.com spokesperson Karen Darby said.
She commented: "Over the past year, wholesale gas prices have fallen by half, with wholesale electricity costs down by almost a third.
"Despite some highly-publicised price reductions, the major suppliers have only brought average bills down by around 15 to 20 percent," she added.
If overall energy prices rose by even ten per cent, 400,000 households would be pushed into fuel poverty, she added.
Meanwhile, British Gas has just undercut rival Scottish and Southern Energy by 32 pence.
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