Health advocates say the repeal of world-leading smokefree legislation last month has set the smokefree target for Māori back by more than a decade.
Jacqui Harema, the chief executive of Māori public health group Hāpai Te Hauora, said it was "devastating".
"I just think the harm that we're going to see for our whānau over the next generations is going to be horrific."
The Māori smoking rate - at 17 per cent - is more than double that of the overall smoking population which sits at 7 per cent.
Under the previous legislation, Māori were projected to reach the smokefree target by 2027 but Harema said modelling suggests it will now be 2040 at the earliest.
And while smoking rates for rangatahi 18-24 have more than halved in the last decade to 3.9 per cent, Harema said this trend might reverse under the new changes.
"Some young people are using cigarettes to get off vaping, as opposed to vaping to get off cigarettes because they don't like the taste of cigarettes.
"So it's a very real possibility that we will have more young people taking up cigarette smoking as well as vaping."
Takiri Mai Te Ata Regional Stop Smoking manager Catherine Manning told The Hui host Julian Wilcox she disagreed with those who celebrated vaping as a tool to stop smoking.
"It wasn't an aspiration of ours to maintain addiction. What we asked for was to eliminate the harm that was being caused by the use of tobacco."
Associate Professor Anaru Waa, from the Eru Pomare Māori Health Centre at the University of Otago, told The Hui the science was still out on how harmful vaping was - particularly for young people.
But he said New Zealand had one of the highest vaping rates in the world.
"We do know just over 22 percent of our rangatahi use vaping daily and that's three times higher than non Māori."
Smoking rates for young people were similar: smoking rates for non-Māori young people were as low as 1 percent but, for Māori youth, it was 3 percent, said Waa.
He described the Coalition Government's changes to smoking legislation as "colour blind".
Smokefree advocate Hone Harawera described vaping as an epidemic "worse than bloody tobacco. Because with tobacco you can smell it from a long way away".
Harawera said Māori mourn the loss of the 650 men from the Māori Battalion lost over six years in World War II. He said statistics show more than 600 Māori die every year from smoking.
"If the numbers are right, in the 100 days that they've been in Government, 200 Māori have lost their lives to tobacco and they're doing nothing - absolutely nothing - to try and change their trajectory."
