By Will Nicholas in Canberra

A government-owned supermarket chain would sell groceries more than 20 per cent cheaper on average, under a plan hatched by a minor party. 

The idea for the federal government to buy up 200 Coles and Woolworths stores and open more than 400 extra shop-fronts has been floated by a Greens-affiliated think tank and given the nod by the party’s freshly minted leader.

The average four-person household would save $60 a week, or $3134 a year, according to the Green Institute’s report, proposing to offer eggs, milk, fruit, vegetables, meat and cheese at about two-thirds of their current price.

The plan would cost $25.1 billion over five years.

“For half the cost of a single AUKUS submarine we could establish a national network of publicly owned supermarkets that would save families thousands of dollars on their groceries,” ex-Greens MP Max Chandler-Mather said on Tuesday.

“It’s common sense that if you want more affordable prices on essentials then you need to cut out the profit with public ownership.”

After the hefty initial bill, the stores would be self-funded, according to the report.

It’s a carbon copy of a policy spearheaded by wildly popular New York City mayor Zohran Mamdani, who is piloting five city-owned grocery stores across the Big Apple with the same objective.

It’s the second time the Greens have ripped a page out of Mr Mamdani’s playbook, after the party’s Victorian arm proposed creating a community safety and crime prevention office combining outreach, mental health, addiction and homelessness services with policing.

More than four-fifths of Australian voters including a majority of One Nation supporters somewhat or strongly support the idea of rolling out state supermarkets to cut the price of groceries, according to YouGov polling commissioned alongside the Green Institute report.

However, just 37 per cent of voters were in the “strongly support” column and those canvassed were not given details about the policy’s costings.

David Shoebridge, who on Wednesday took over as Greens leader after Larissa Waters stepped down due to ill-health, has said the policy merits discussion.

The NSW Senator is under pressure to turn the party’s languishing popularity around as One Nation surges on right and progressive movements gain traction overseas.

While populist left leaders like Mr Mamdani and the UK’s Zack Polanski make good headway in the polls, the Greens have barely moved from the 12 per cent vote share they scraped together at the 2025 federal election.

Mr Chandler-Mather, the former Greens politician at the helm of the public grocery store policy, lost his Brisbane seat back then, along with two of his lower-house colleagues, including the party’s then-leader Adam Bandt.

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