Plans to make it a criminal offence to manipulate the energy market will provide a "stronger deterrent" against the practice, Energy Secretary Ed Davey said.
Anyone found guilty of rigging wholesale gas and electricity prices could face up to two years in jail under new proposals.
"Manipulating the energy market is absolutely unacceptable, and these proposals provide a much stronger deterrent - more in line with the approach taken in the financial markets," Mr Davey said.
The Energy Secretary said the government was doing "everything it can to help consumers" with their energy bills.
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