Two of Australia’s former competition chiefs, Graeme Samuel and Rod Sims, say the Albanese government’s threats to shake up supermarkets’ dealings with suppliers is unlikely to reduce the final price of groceries.

With Coles slashing the price of its beef, lamb and some 300 other products, and official figures putting inflation below estimates at 4.3 per cent in November – the lowest for nearly two years – the government announced former competition minister Craig Emerson would lead a review into the code of conduct signed by the four biggest retailer groups.