Icecream makers are worried by revelations that the Auckland Council is negotiating a 10-year deal to give Tip Top selling rights at public pools, parks, the waterfront and events.
Rival firms fear being shut out of places like Auckland Domain and the waterfront where icecream sales do a roaring trade in summer.
"Tip Top are going to cream it and take out the opposition in Auckland," said one competitor.
New Zealanders are among the biggest eaters of icecream in the world, getting through an average of 22 litres each every year.
Brett O'Riley, who heads the council's economic arm, says there are no plans to give Fonterra "blanket exclusivity" to sell its Tip Top icecream.