Helgesen said that the Justice Ministry concluded that “there is no legal basis” for allowing hunters to target four wolf packs in Hedmark.
The ministry has therefore cut the hunting quota from 47 to 15 wolves.
The government had announced in September that the 47 wolves could be hunted in a move that was hailed by farmers but decried by environmental groups outraged that such a large proportion of the 65-68 registered wolves in Norway would be fair game for hunters.
"This is pure mass slaughter," Nina Jensen, the head of the Norwegian branch of the World Wide Fund for Nature (WWF), said at the time. "We haven't seen anything like this in almost 100 years, when the policy at the time was to exterminate all the big predators.”
On Tuesday, Jensen took to Twitter to personally thank Helgesen for “standing up for nature”.
The course reversal came just days before the hunting season was scheduled to begin on January 2nd. Nearly 300 hunters had planned hunts for the four wolf packs that have now been spared.
Of the 15 wolves hunters are still allowed to take, six have already been shot.
The Norwegian wolf population currently has seven packs with one reproductive couple, which is "above the national population target" since each pack can be expected to deliver a new litter every year, the Norwegian environmental agency said.
Wolves are listed as "critically endangered" on the 2015 Norwegian list of endangered animals.