The Greens are promising smaller grocery businesses aren't the target of an attempted price gouging ban.
Its new member's bill would make it illegal for supermarkets to charge excessively above reasonable profit margins.
The Commerce Commission would set this threshold, and take rule breakers to court.
Green Party co-leader Chlöe Swarbrick says the big supermarkets are making all the money - and everyday Kiwis are paying the price.
"What we're talking about is excess profits. They are still able to, obviously, make reasonable returns."
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