"The number of disposable nappies going to landfill or ending up as litter is a key contributor to this," she said.
In New Zealand, "only 8 per cent [of people] are cloth users but we think that by making more sustainable options more widely available and affordable, this will only continue to grow as these more environmentally conscious choices become a reality for customers".
The shift follows a move earlier this year to ban plastic shopping bags throughout New Zealand.
The ban, which started in July, prohibited retailers from supplying single-use plastic bags and those who do could face a fine of up to $100,000.
Countdown's general manager of corporate affairs, safety and sustainability Kiri Hannifin. Photo / Supplied It also resulted in a number of Countdown supermarkets facing a shopping basket shortage as shoppers fled with the prized grocery carrier.
Elsewhere, it was hoped a new returns scheme for drinks containers would see Kiwi recycling rates lift from around 50 to 80 per cent.
An estimated two billion single-use beverage containers are sold in New Zealand each year with only about half of them recycled.
But work had begun on a container return scheme (CRS) that aimed to significantly change the way bottles are recycled.
Meanwhile, Little & Brave co-founder Semisi Hutchison said they were delighted to work alongside Countdown to help reduce plastic waste.
"Kiwis want sustainability, but also want ease-of-use, convenience and effectiveness.
"We believe our products bring this to the consumer and we are excited to watch them vote with their purchasing dollar.
"After all, making sustainable change now for our little one's future is one of our founding values."