Coca-Cola Amatil will distribute a range of beers on the New Zealand market as a step into the Australian brewing industry.
But opponents say New Zealand doesn't need any more alcohol.
Coca-Cola Amatil will distribute Canadian-based Molson Coors' range of beers in New Zealand including Coors Light, Carling, Caffrey's and Cobra.
The move is part of a larger plan by Coca-Cola Amatil to re-enter Australia's billion-dollar brewing industry by 2014.
At the company's annual general meeting this week, investors were told of Coca-Cola Amatil's six-step plan.
The company says it will start distribution for Molson Coors in New Zealand "from mid-2012" with a plan to re-enter the Australian brewing industry two years later.
Alcohol Healthwatch director Rebecca Williams last night said: "We need more alcohol like we need a hole in the head."
"Any new brand will be accompanied by aggressive marketing strategies," Ms Williams said.
"Alcohol is causing a significant problem already and we're grappling with getting the best answers."
Coca-Cola Amatil told investors this week it would enter New Zealand's market with "international partners", the first being Molson Coors.
A Molson Coors spokesman in the UK said it was the first time the company's beers were to be sold in New Zealand.
Coca-Cola Amatil is the Australian-based bottler and distributor of Coke and other soft drinks.
The company's six-point plan to break back into the Australian brewing industry includes new strategic partnerships with Fiji-based beer brands.
The company believes there is more than A$1 billion ($1.29 billion) a year to be made in the Australia and Pacific region and a further A$200 million in the premium beer market.