Unleaded petrol prices in most capital cities have risen by the most in four months, with the average prices above $1.40 a litre, according the new analysis released by CommSec. 

The Australian Institute of Petroleum has also announced that the average retail petrol price was 139.9 cents last week compared to the average wholesale petrol price of 115.2 cents, increasing the gross retail margin from 10.6 cents to a record-high 24.7 cents a litre. 

“The national average Australian price of unleaded petrol rose by 5.8 cents to 139.9 cents a litre- the biggest weekly increase in four months,” the report said. “Prices of $1.20- $1.30 a litre appear to be in the rear vision mirror for most motorists in the near term.” 

Sydney has experienced an increase of 13.1 cents a litre, while Melbourne and Brisbane experienced an even higher increase of 15 cents and 16.7 cents respectively. 

“Pump prices have begun lifting in some capital cities for the first time in six weeks. And rising global crude prices imply further increases are likely in the weeks ahead,” Ryan Felsman, the CommSec senior economist said. 

Mr Felsman also commented that the profit mark-up of 24.7 cents a litre was “unusual”, as the average mark-up was usually 10 to 15 cents a litre. 

“Generally what happens in that if oil prices lift, it takes some time for prices to be passed on to consumers,” Mr Felsman said. “Instead, pump prices increased almost immediately.” 

CommSec estimates more fuel price increases in the lead-up to Christmas.