Legislation aimed at banning misleading supermarket offers is set to be introduced by former Cabinet minister John Denham.
The Labour MP's proposals would require supermarkets to release pricing data, showing how much a product costs on a store by store basis.
He said the move would "put an end to misleading pricing practices and dodgy deals" such as artificially raising the cost of an item for a short time only to return it to its original value and label it as a special offer.
Mr Denham is to introduce his Supermarket Pricing Information Bill in the Commons.
He said: "In tough times, when living standards are falling, shoppers need every help to get the best value for money. My Bill will even up the relationship between supermarkets and the consumer.
"Supermarkets collect and analyse data on shopping habits to shape their pricing and promotion policies. Yet many consumers are still left shopping around from store to store to get the best deal in much the same way they did decades ago.
"Consumers will quickly be able to compare the price of their shop to get value for money, the release of this data will put an end to misleading pricing practices and dodgy deals. They will also be able to see where branches of the same supermarket charge significantly different prices."
He claimed that price transparency would reduce the need for costly investigations by the Office of Fair Trading. "The OFT's role is important but it would be much better if dodgy pricing was driven out of the system by consumer power," he said.
Mr Denham will introduce his proposals as a ten-minute rule motion.
Although his Bill has support from MPs on all sides of the Commons and campaign groups including Which?, it is unlikely to make further progress without Government backing.