Fines will be issued to any of the Big Six energy companies which fail to return money to former customers, a Government source has told ITV News Consumer Editor Chris Choi.
Energy: Firms have £400m of customer money they are not entitled to they should "expect fines" government source tells me
Energy regulator Ofgem has written to the leading providers calling on them to refund the more than £400 million found to be held in closed accounts.
More top news
Analysis from the Home Office suggests as many as 13,000 people may be in slavery in the UK - much higher than previously thought.
A headteacher has reportedly warned "snowplough" parents are so over-protective that their children end up unable to deal with failure.
The largest horse chestnut tree in the country declared as the 300-year-old specimen at the estate where PM Benjamin Disraeli once lived.