The tide looks to be changing for Gull as the leader of low-priced petrol offerings.

Fuel-finding app Gaspy is reporting Taupo's Gull Ātiamuri has been undercut by Z-Energy's Waikaraka U-GO in South Auckland.

AA Principal Policy Advisor Terry Collins says Gull paved the way with its New Zealand- owned self-service model. 

He explained it has a low cost entry, with electronic payment options meaning stations don't need staff - and the fuel's there. 

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