Angus MP Mike Weir has called for the UK Government to step in after British Gas became the latest energy company to increase its tariffs.
The SNP energy spokesman is concerned at the announcement that it will put up its gas bills by an average of 18% and electricity bills by 16% from August 18.
The announcement follows a similar price hike by ScottishPower last month and other energy companies are expected to follow suit.
The higher bills will affect nine million households and cost an extra £190 a year. British Gas has blamed the increase on rising global energy prices, which have risen by 30% since last winter.
It said its customers could benefit from free loft and wall cavity insulation, free energy use monitoring, and flexible payment terms.
Mr Weir said, “There is a limit to which people can keep absorbing massive energy price increases like this. The UK Government has a duty to step in.
“Until there is a top-level review of the domestic and international energy market, domestic customers will continue to suffer.”
British Gas managing director Phil Bentley said, “We know there is never a good time to raise prices, but we are buying in a global energy market and have to pay the market rate.”
Consumer Focus chief executive Mike O’Connor said wholesale prices have gone up but are still a third lower than their peak in 2008. He has calculated that in this time British Gas prices have risen by around 44% on gas and 21% on electricity and suppliers have made healthy profits.
He added, “This price rise will send a shockwave across the country. The impact on customers will be severe, piling more pressure on severely stretched household budgets and pushing hundreds of thousands more households into fuel poverty.”
Energy regulator Ofgem has called for the industry to be overhauled after it found the big six companies were putting prices up more quickly than they reduced them when prices fell.