Canberra drivers missed out on falling petrol prices and the cost of fuel is now almost 10c a litre above the metropolitan average.

The latest figures from the Australian Institute of Petroleum showed the average price of unleaded in Canberra was 149.8c a litre last week - the same as the previous week.

However, the metropolitan average fell by 4.2c to 140c a litre, partly because of a 5.5c fall in Sydney (to 138.3c) a 6.4c drop in Brisbane (to 140.3c) and a 5c decrease in Adelaide (to 137.6c).

CommSec economist Savanth Sebastian said the fall in the national average wound back some of the almost 7c a litre increase recorded the previous week. He is not expecting any changes this week.

"Not only are global oil prices relatively stable but the Aussie dollar has held up well. Overall CommSec expects pump prices to track sideways over the next fortnight," he said.

"From a longer-term sense the shifts in the Australian dollar are going to play a vital part in the direction of petrol sign boards across the country. CBA currency strategists expect the currency to head towards US108 cents over the coming year – a result that should ensure further savings for motorists if the global oil prices remain around current levels."