The World Trade Organisation in Australia has rejected claims that plain packaging measures hurt trade, saying they're a legitimate public health measure.
Although the WTO's final ruling is not expected until July, a confidential draft said Australia's laws were a legitimate public health measure, according to Bloomberg reports.
The ruling is expected to give the green light to other countries to roll out plain packaging laws.
Maori Party Co-Leader Marama Fox says the ruling is "fantastic for New Zealand."
New Zealand has already passed plain packaging into law, and Ms Fox says we could see it rolled out after the election.
She is hopeful that there won't be any legal challenges.
Ms Fox says the WTO's ruling "will be a huge signal to all other corporations that they cannot hold a country to ransom, especially when they're making policy for their own public health."
Auckland University associate professor in public health Dr Natalie Walker says it's time for us to follow Australia's lead, but she still expects a fight from the tobacco industry.
"Hopefully New Zealand will follow Australia's lead and look to introduce plain packaging as well, but we know from past experience that the tobacco companies will fight it tooth and tail, this is their worst nightmare and they will not be happy with this ruling.
"It doesn't matter what Australia's done, they will still try and fight."
Dr Walker says the WTO decision could also lead to more pressure to introduce plain packaging for alcohol and fast-food.
She says University of Auckland research has found that plain packaging and warning labels are effective in deterring people from sugar sweetened beverages.
The packaging "has a huge impact" and the products were perceived as less cool, less attractive and of lower quality.
Dr Walker says there's also a "small amount" of overseas research showing the same trend with plain packaging on alcohol.
She also says plain packaging on New Zealand tobacco products "could dramatically reduce smoking related illness, hospitalisations and death. It could potentially have a huge impact."