NEW FIGURES from the Australian Institute of Petrol this week show that the national average price of petrol has risen to 121.80 cents - up 0.3 cents in the past week.
Nearing a three month high, the average metropolitan price rose in the past week by 0.7 cents, reaching 121.50 cents.
Regional areas however have seen the price of petrol drop 0.3 cents to 122.50 cents.
Commonwealth Securities economist Savanth Sebastian said that the direction of petrol prices in the short term is far from certain, but that the national average is likely to sit around 120 to 125 cents per litre.
"The wholesale price fell over the first three days of last week before once again edging higher. Also the Australian dollar has been increasingly volatile in recent weeks," Mr Sebastian said.
Thursdays Best Value For Filling Up
Thursdays are now the cheapest day to buy petrol, according to the RACV.
Weekly price cycles have in the past shown that fuel has often been the most affordable on Tuesday and early Wednesdays. A new shift in pricing cycles has seen Wednesday afternoon and Thursday morning become the best time to buy petrol.
According to RACV chief engineer Michael Case, the change was "progressive and subtle," with petrol now up to 12 cents cheaper to buy on a Thursday morning.
NRMA President Wendy Machin told radio station ABC 702 that the reasons for the difference in price are unclear.
"It doesn't happen in any other city in the world," Ms Machin said.
"We've tried to find out why we get this up and down. It used to be cheaper on Tuesdays, a few years ago we moved to Wednesdays and now quietly it has just started to move across to Thursday morning over the last few weeks."
In related news, the Australian Federal Government has asked the ACCC to investigate possible price fixing in the petrol retail market, concerned that petrol companies may have been colluding to set a weekly price cycle.