WHAT Independent Senator Nick Xenophon calls "predatory discounting", the mouthpiece for Australia's major shopping chains calls better competition.
Mr Xenophon wants to make it illegal for companies including Woolworths and Coles to use "shopper dockets" because it risks putting competitors out of business.
His discussion paper on the topic was released on Wednesday, although he plans to introduce legislation to properly address the issue.
Mr Xenophon said he received complaints from independent retailers saying the major grocery chains were cutting fuel prices by 40 to 45 cents per litre.
"Consumers might think they're getting a bargain but if smaller retailers go under, that reduces competition and we all lose in the end," he said.
The change would make predatory discounting an abuse of market power.
Woolworths referred questions to the Australian National Retailers Association while Coles failed to respond before deadline.
ANRA chief executive Margy Osmond - whose group represents the major supermarkets, Harvey Norman, Bunnings and Costco - said the discounts helped people manage their cost of living.
"Fuel retailing continues to be a very competitive market, and this competition is continuing to drive lower prices for the Australian community," Ms Osmond said.
Senator Xenophon's bill could be introduced before the end of November.
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