People found guilty of rigging wholesale gas and electricity prices could face up to two years in prison under new government proposals.
Currently regulators can investigate and fine people who have manipulated the market, but Energy Secretary Ed Davey said he wants to make it a criminal offence.
New laws would make it illegal to fix energy prices at an artificial level or use insider information to buy or sell energy on the wholesale market, with offenders facing a jail term and a criminal record.
The move is aimed at safeguarding consumers and providing a "stronger deterrent" against abuses, the Department of Energy said.
More top news
Ruth Smeeth is due to give evidence at a hearing involving party member Marc Wadsworth.
In the latest in the franchise, Marvel's superheroes assemble en-masse to face their biggest challenge yet.
Brexit Secretary David Davis has insisted EU opposition to UK proposals on the Irish border are no more than an ‘opening position’ in negoti