Australian motorists are set to benefit from further falls in petrol prices in the weeks ahead, as global oil prices wane and the local currency remains strong.

Figures from the Australian Institute of Petroleum show the national average price of unleaded petrol fell by 3 cents to $1.48 per litre last week.

That is its lowest level in four months.

CommSec chief economist Craig James says there is scope for another 3 cent drop in the next two weeks.

"Consumers are very, very cautious about spending their money, and if there's a few extra dollars back in their wallet, if the petrol price is falling rather than rising, that tends to improve people's confidence levels," he said.

"It gives them a greater purchasing power, and hopefully for retailers' point of view - that means greater spending at shopping malls and the like."

The Australian dollar has climbed back above 96 US cents, after reaching as high as 97 US cents last week.

At 3pm (AEST), it was worth 96.06 US cents.

West Texas Crude oil is trading at $US97.35 a barrel, while Tapis Crude is at $US114.92 per barrel.

Wholesale and retail price gap 'still too high'

Mr James says there has been a fall in the margin petrol retailers are making on sales in recent weeks, but he believes the gap between retail and wholesale prices remain too high.

Earlier this month, the gap grew to 13.9 cents per litre - just below the highest level on record.

Last week it fell to 11.3 cents per litre.

Mr James says fuel retailers appear to be making excessive profits at a time when motorists should be enjoying far better savings on petrol.

"That's still above the longer term averages and if we saw further easing in that gap, that margin, then that would provide even more savings for Aussie consumers," he said.