David Cameron has told MPs energy prices are not falling as fast as he would like to reflect the fall in oil prices.
The Prime Minister's comments come as a new survey claims three in five older people will ration their heating this winter amid fears over bills.
Energy Secretary Amber Rudd has called upon power companies to "look after their consumers" and put bills down, following a drop in wholesale energy prices.
"I'm saying look after your consumers. Look at the evidence. We need to see these prices come down," Ms Rudd told ITV News.
Three in five older people will ration their heating this winter amid fears over high energy bills, according to a new survey.
Older people have been warned to keep their homes warm and get a flu jab as weather experts warn of a cold snap.