He also commented that the government would be looking to stamp out any practises of unfair charging, speaking with reference to some consumers paying higher charges for using pre-payment meters.
Mr Miliband, discussing the reducing of wholesale costs worldwide, said: "We've recently seen big falls in wholesale gas and electricity prices, but I understand that because energy companies tend to buy in advance they won't be passed on immediately."
"But they must be passed on as soon as possible," he added.
Labour Member of Scottish Parliament Duncan McNeil recently told the Herald he would be "demanding" that energy firms reduce their prices.
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