Petrol prices rose almost 10 per cent to a four-year high across Australia's five major cities last financial year, with the average price at the bowser hitting $1.35 a litre.

The Australian Competition and Consumer Commission’s latest petrol monitoring report found the average annual petrol price had jumped from an average $1.22 a litre in 2016-17.

Last financial year's $1.35 a litre is the highest average petrol price since 2014-15, when prices reached $1.40 a litre.

Brisbane had the highest petrol prices over the year, at an average of $1.37 a litre. Melbourne was the second most expensive city for petrol at $1.36, while Sydney had the cheapest petrol for all capital cities at $1.32.

During the June quarter, average prices fluctuated from a low of $1.38 a litre up to $1.54 a litre.