The Australian Competition and Consumer Commission (ACCC) will begin a series of public hearings for its inquiry into the supermarket sector.
Consumer advocacy groups and supplier representatives are first up, with Choice and the Australian Food and Grocery Council set to attend on Thursday.
"We have received a large volume of information ... and these hearings will provide an opportunity for us to seek clarification on a range of the very complex matters," the commission's deputy chair Mick Keogh said.
Aldi, Metcash, Woolworths and Coles will all appear at the hearing in coming days.
Assistant Minister Andrew Leigh is confident the hearings will lead to better deals for shoppers. (Lukas Coch/AAP PHOTOS)
Assistant Competition Minister Andrew Leigh said the hearings would ensure people got a better deal at the checkout.
"The government understands the pressure Australian families and farmers are under," he said.
"These public hearings will provide an opportunity for supermarket CEOs to answer concerns regarding treatment of suppliers and increasing prices at the checkout."
Hearings are also set to examine price-setting practices, retail competition, supply chain concerns and the profit margins of major chains.
Coles and Woolworths have come under fire as Australians accuse them of benefiting from the cost-of-living crisis.
The federal government has vowed to take action, announcing in January it would set the consumer watchdog for the supermarkets and directing the ACCC to conduct an inquiry into the sector.
Many consumers have lost trust in supermarket pricing while suppliers have said they are forced to agree to unfavourable terms, according to the commission's interim report.
Major supermarket chains will have representatives at the watchdog hearings. (Darren England/AAP PHOTOS)
A final report on the inquiry is due to be delivered to the government by February.
Dr Leigh said a mandatory code of conduct, which governs the relationship between supermarkets and suppliers, will soon come into effect, saying the previous voluntary code was "toothless".
"The Albanese government will introduce legislation later this month to attach significant penalties for supermarkets that breach the food and grocery code," he said.
"We are calling for bipartisan support on this important bill."
Multimillion dollar penalties would be imposed on supermarkets who breach the code under the proposal.
It comes as the ACCC in September launched a court case against Coles and Woolworths, claiming the retailers had misled customers with illusory discount schemes.
Both grocers deny the allegations and say the legal cases against them are misconceived.
The federal government will provide $30 million in extra funding for the ACCC to continue investigations and enforcements in the supermarket and retail sector.
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