Asthma and Respiratory Foundation (ARFNZ) board member Richard Edwards, a public health physician, said it was "outrageous" the Government would allow an Imperial Tobacco factory based near Wellington to continue to make cigarettes.
"Smoking is an ongoing health emergency," he said.
"This decision is particularly unfortunate given the emerging evidence that Covid-19 infections may be more severe among smokers, and flies in the face of the Government's commitment to achieve a Smokefree Aotearoa."
Ms Ardern dismissed the idea of amending the Government's advice, saying the immediacy of the lockdown demanded swift action.
"We haven't gone in to the specifics of every individual part of a supply chain for a supermarket," she said.
"We shut down New Zealand in a 48 hour period."
"We kept the guidance very simple; if you supply to our supermarkets, you are able to continue to produce supplies for our supermarkets."