Unleaded petrol at the United Service Station in East Maitland was selling for 116.7 cents a litre yesterday – well short of the 137.9 cents a litre being charged in Jindabyne in the Snowy Mountains.

At Caltex East Maitland the price was 116.9 cents a litre and at Shell Maitland it was 119.9 cents a litre.

In South Australia, unleaded petrol sold for 124.9 cents a litre in Port Augusta and 139.9 cents a litre in Whyalla.

In Queensland, it sold for 133.2 cents a litre in Mt Isa and in Western Australia it ranged from 124.9 cents a litre in Bunbury to 142.9 cents a litre in Esperance.

And according to market analyst Commsec, the price of petrol is heading for $1 a litre.

Commsec said the global slide in the price of crude oil has combined with a steadying Australian dollar had seen the price fall more than 20 cents in the last three weeks.

"Motorists across capital cities should not be surprised to see pump prices nearing $1 a litre," Commsec economist Craig James said, once shopper docket discounts are taken into account.

Fresh data from the Australian Institute of Petroleum shows the unleaded pump price fell by 7.4 cents in the last week.

The national average for unleaded petrol is now $1.26 a litre.

"Pump prices are expected to fall by at least 10 cents a litre in the next fortnight following on from falls in wholesale prices," Mr James said.

He reckons motorists could soon be paying about $70 less each month – equal to an interest rate cut of half a percent point on an average mortgage.