He said that consumers currently get "a raw deal" in the quest for cheap gas.
Mr Cullum called for an energy efficiency scheme to be rolled out across the country in order to help take people out of fuel poverty.
He added that such a programme could also create employment opportunities.
Consumer Focus is a statutory organisation - not a regulator - that works for consumers' rights and to voice their concerns.
Its powers include the capacity to make a "super complaint" when services are very poor and it also carries out research for consumer interests.
Many people may welcome the new law and hope this eventually results in cheap gas bills.
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