Fuel companies need to tell the public why their margins are creeping higher though oil costs are dropping, the AA says.
AA petrol watch spokesperson Mark Stockdale told TV ONE's Breakfast there is a lag between what fuel companies pay for petrol and what consumers pay at the pump.
"Over time margins are certainly increasing," he said.
"If the fuel companies are saying historically margins haven't been high enough, then they need to go to the public and explain why they think margins should be rising."
Stockdale's comments follow BP's claim that the company gets bad press even though prices have fallen back under $2 for the first time in nearly a year.
BP's External Affairs manager Jonty Mills told TV ONE's Breakfast yesterday that "there's a bit of scepticism out there and it's hard for us to get a good rap in the media".
"However I think we've shown, we've dropped the price six times consecutively in the last month and a half. BP have led four of those," he said.
One of BP's rivals, Gull, further cut prices for regular 91 Octane petrol to $1.959 today.
But Stockdale said the rise in margin of three to four cents in the last couple of months is "too much too soon" and he does not understand what has happened over that period to justify it.
Though petrol cuts have been coming "thick and fast", Stockdale still thinks Kiwis could be paying too much at the pump.
"We're basing it on the margin as it was in March, and based on those numbers we think there could be a cut of about three cents per litre," he said.
Stockdale thinks there should be another price cut within the