A health group has lodged a complaint with the ombudsman, after failing to receive information about the repeal of the smokefree law.
Last month, RNZ received leaked information showing that the Associate Health Minister Casey Costello sought advice on freezing the annual increase in tobacco tax.
The MP said she had not sought advice but later apologised.
A public servant, who the Health Ministry says leaked the information, has lost their job.
In a statement, Health Coalition Aotearoa (HCA) said it applied through an Official Information Act request for more information about the repeal of the smokefree law, but was blocked by the ministry.
It is arguing that public interest in the repeal, far outweighs other considerations.
"HCA believes the New Zealand public has the right to know about proposals and advice sought by and provided to the relevant Minister when the topic is of vital public interest, and particularly in relation to legislation that is being passed under urgency," the statement said.
"Costello's request for advice on a proposal to freeze excise tax on tobacco mirrors the objective sought by the tobacco industry," it said.
The coalition said the proposal could be considered a breach of the World Health Organisation's Framework on the Convention for Tobacco Control which New Zealand is party to.
The government plans to repeal the Smokefree law (2022) within its first 100 days or by 8 March, 2024.