A giant tobacco company is still hoping to talk the government out of legislating for plain packaging of tobacco products.
Imperial Tobacco's global director of corporate affairs, Axel Gietz, is in New Zealand as submissions close on the proposed law change.
He said plain packaging had been introduced in just one country, Australia, where it had provoked a lot of illicit trade in cigarettes.
And there was no evidence it had affected cigarette consumption there, he said.
"The government itself says that whatever impact on consumption it has had cannot be attributed to the Plain Packaging Act because at the same time Australia also introduced excessive tax hikes of 12.5 percent per year every year for four years running."
Mr Gietz said plain packaging and tax hikes encourage criminals who do not have to obey the rules and do not pay taxes.
Draft regulations were unveiled earlier this month that would replace tobacco imagery with plain green-brown packaging, and the government said plain packaging would be legally required by the end of the year.
Imperial could sue
Mr Gietz said Imperial Tobacco - the world's fourth largest tobacco company - could not rule out suing the government if plain packaging goes ahead.
He said the brands were part of the intellectual property of tobacco companies, and litigation was an option open to them if the government does not change its mind.
"Legal action is always a last resort but you have to understand that our brands are one of the three key assets of our business, along with our people and with our factories.
"When one of the key assets is taken away or threatened to be taken away (from) us, of course we have to, in the end, consider legal action to defend our rights to our intellectual property."
In 2015 another tobacco company, Phillip Morris, sued the Australian government over the same issue, but lost the case in the Australian High Court.
Meanwhile Maori Party co-leader Marama Fox walked out at the end of a televised debate with Mr Gietz after telling him he should "crawl back into the hole that is reserved for the corporate executioners", TV3's Newshub reports.
Ms Fox removed her microphone and left the set after a sometimes acrimonious discussion on The Nation programme.