The US Chamber of Commerce and business groups have launched a blistering attack on the government's plan to enforce plain packaging on tobacco.
Associate Health Minister Tariana Turia this week announced a ban on branded packets as part of a bid to get New Zealand smokefree by 2025.
Tobacco giants - which are fighting similar restrictions in Australia - have vowed to oppose the move.
There are fears the branding ban violates intellectual property rights, could open the floodgates for expensive lawsuits and jeopardize a number of free trade deals.
This morning the US Chamber of Commerce issued a joint statement with other business interest groups calling for the Government to "place the effort in the well-intentioned, yet ill-advised, category."
It says the tobacco industry's "legitimate trademark protection and branding" are "rights long protected under law and international treaties."
In a thinly veiled threat, the statement went on:
"New Zealand has long called upon trading partners to avoid arbitrary measures not sufficiently grounded in science when regulating industry... We hope the New Zealand government will consider the concerns we have raised for the possible impact on New Zealand exports, such as dairy and wine, should other governments feel emboldened to take similar measures."
It was also signed by the TransAtlantic Business Dialogue, the Emergency Committee for American Trade, the National Association of Manufacturers, the United States Council for International Business and the National Foreign Trade Council.
The Australian government is currently embroiled in a high court battle with the tobacco industry over its new legislation - due to come into force in December.
Two countries - Honduras and the Ukraine - have lodged complaints with the World Trade Organisation.
But health advocates say the ban will sever customer's brand loyalty and deter young people from buying into cigarette firms' aspirational advertising.
The Government will introduce legislation once a public consultation exercise is complete.
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