Australian grocery retailer Metcash Trading has unveiled its discount fuel offer, which is being launched to compete with deals already offered by rivals Woolworths and Coles Myer.

Consumers who spend more than A$30 (US$20.1) at any of Metcash's 189 Independent Grocers of Australia, or IGA, stores in Queensland, will be offered a 4 cents per litre discount on fuel.

"We expect this offer will shake up the petrol and retail market in Queensland, as smart shoppers will gain genuine discounts if they simply present a receipt of their fuel purchase when they shop at their local IGA store," John Hockings, a board member of IGA Queensland, was quoted by Dow Jones News as saying.

Metcash said it expects to roll out the discount fuel programme to the other 1,000 IGA stores in Australia in the near future.

The discount is currently only available in stores on Fridays, but Metcash said it may consider extending it to the rest of the week.