Independent MPs Bob Katter and Andrew Wilkie have donned the greedy pig suits to get attention (and it worked) for their bill to reduce the dominance of the Coles and Woolworths supermarket duopoly.

The big two supermarkets control 65 per cent of Australia's supermarket sector, but attention has turned to their large profit margins and corporate behaviour during the cost-of-living crisis.

Prime Minister Anthony Albanese recently stated, "quite clearly they have excessive market power".

In a case of saying "I told you so", the legislation the two independents are pushing in pink was introduced 10 years ago but did not get major party support to pass. They are planning to re-introduce an updated version of the bill.

The bill would force the major supermarkets to divest their market power in the grocery sector to a maximum of 20 per cent within five years and create the position of a Commissioner for Food Retailing with functions to stop price gouging and other anti-competitive behaviours.

It would also scrap the Food and Grocery Code of Conduct as the two MPs regard it as failing to address power imbalances between the giant companies, suppliers and producers.

There are three inquiries into supermarket behaviour. There is a a Senate inquiry, the Australian Competition and Consumer Commission is examining prices and competition, and former Labor minister Craig Emerson is reviewing the Food and Grocery Code.