A Thailand cannabis company believed its low-priced imports may eventually undercut New Zealand's cannabis market, and investors were not being properly warned.
But New Zealand's current draft laws proposed a ban on imported cannabis.
Jim Plamondon of the Thai Cannabis Corporation said "eye-popping estimates" from analysts, combined with the potential passage of legalisation of cannabis after next month's referendum, had attracted the attention of New Zealand's investors and policy-makers.
The potential retail value of New Zealand's medical cannabis was estimated to be worth $360 million a year and taxes at $490 million.
New Zealand's Business and Economic Research agency Berl estimated the potential retail value of all cannabis at $NZ1.5 billion annually.
Plamondon said estimated excluded the impact of low-priced imports.
"If the presumption is, that the economic benefits of cannabis legalisation will boost the economy and help lift it out of the recession, that's almost certainly not going to be true.
"And in fact, almost all the money poured into the New Zealand cannabis industry is likely to go right down the gurgler."
But Berl said as the law stood now, imported product - except for cannabis plant seeds, would not be allowed.
Research director Dr Ganesh Rajaram Ahirao (Ganesh Nana) said the scope within which Berl undertook estimates for the Ministry of Justice, was that the proposed cannabis market would be strictly regulated at all stages from production, processing, and supply.
Berl understood that there was no intention (or allowance) for importation of product except for cannabis plant seeds.
"Furthermore, given the strictly regulated market approach adopted, the market allocation will explicitly state how much is allowed to be grown, while low-priced products will be excluded," he said.
"In this light, we do not see how the impact of imported cannabis is relevant to our estimates of market size."
Plamondon expected laws drafted in anticipation of recreational cannabis being legal would eventually change to allow cheaper, imported products.
He said New Zealand was his company's first export target market.
"We expect to sell it there within two years. It's clear there are a few key points of entry that will bring us into the market and they're very keen.
"I've corresponded with several who are very keen to have an equivalent product at one tenth the price - who wouldn't be?"
A private capital-raising firm, Snowball Effect, recently warned investors not to put any money into marijuana they were not willing to lose.
Director Bill O'Boyle said the comments related to the infancy of the industry, uncertainty around the new legislation, the expenditure that was going into some of the early businesses and the market size.
"Ultimately there is the supply of the raw product and competition for that supply, and the other concern is delivery of that product into an end market.
"The large uncertainty we see is whether GPs are going to be prescribing any medicinal cannabis products in the near future, and if so - how long might it take to come online."
RNZ reported this week that two years after medicinal cannabis was made legal in Britain many doctors were still not prescribing it, and while it was early days, New Zealand doctors appeared to be in the same camp.
O'Boyle said in relation to the warning from the Thailand company, people needed to refer to the legislation and what it allowed.
"Without commenting directly on what that legislation is, we would want our investors to have a long, hard think about what exactly the parameters are of the company they're looking to invest in.
"The question we'd have, regardless of where the product has come from, is how to compete with a commodity product and produce at scale, in a market which is very small.
"I have no doubt there will be players offshore looking down here to sell their products, if they're allowed to do so."
A Nelson-based medical cannabis firm, Medical Kiwi has already sold its first two years of production to Hektares, a global player in the medical cannabis industry, equating to $30 million for 2021, and $60 million in 2022.
It recently launched a crowdfunding campaign to raise $2 million to get production underway in Christchurch and help fund its Nelson development and technology purchases.
Co-founder and chair, Aldo Miccio, said Plamondon's statement was interesting, especially around Thai product being potentially a tenth of the cost of New Zealand cannabis.
"There are reasonably good margins involved - which is why a lot of people are investing, but we aim with our pricing to be way cheaper than products imported at the moment."
Miccio said cannabis grown outdoors, such as that at grown at tropical altitudes in Thailand was certainly cheaper to produce, but only indoor-grown product would pass the scrutiny of pharmaceutical standards.