Michael McCormack encouraged drivers to "name and shame" petrol stations who were overcharging their customers at the pump.

"Too often, regional motorists bear the brunt of higher fuel prices and I'm making it clear the government expects retailers to make things right and pass savings on immediately," Mr McCormack said.

"With world oil prices plummeting to just over $20 per barrel, regional, rural and remote Australians must receive the benefits of lower prices at the bowser."

Across Wagga petrol prices differ wildly from service station to service station, with the cheapest being found at Tolland Auto Port at 107.5 cents per litre and the most expensive tank of fuel costing 131.9 at a Caltex.

NRMA spokesman Peter Khoury said it was unusual to see such large price disparities in regional Australia, with only some service stations dropping their prices in line with its real market value.

"The gap between the cheapest and most expensive is what you tend to see in places like Sydney, not in Wagga," Mr Khoury said.

"Before you fill up in, get on the NRMA app or the government fuel website because there are huge discrepancies in Wagga and the average is still too high."

The Australian Consumer and Competition Commission chairman Rod Sims said he was "outraged" at the price gouging behaviour he had seen, saying petrol prices should by rights be around 110 cents per litre.

However the real value of petrol is expected to drop even further, as the price war between Russia and Saudi Arabia continues and demand is slashed worldwide in light of the coronavirus shutdown of whole economies.