Supermarkets could cop multi-million dollar fines for unfair treatment of smaller, local suppliers. 

The Government's new grocery code of conduct has been released requiring chains to pay suppliers in a short time span, and engage in good faith. 

The new rules will initially apply to Woolworths and Foodstuffs - coming into force on September 28. 

Consumer Affairs Minister Dr Duncan Webb told Mike Hosking this comes in the wake of a Commerce Commission report calling for a crackdown. 

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