Justice Minister Andrew Little has confirmed that the referendum on recreational cannabis use will be at the 2020 election and will be binding.
He said the question to be asked still needed to be worked out.
A referendum on recreational cannabis use on or before the 2020 election is part of the Labour and Greens confidence and supply agreement.
Speaking to media this morning, Little said this morning that Cabinet has agreed the referendum will be held in the 2020 election and it would be binding.
"There is a bit of detail still to work through, but we are telling the electoral commission that's when it's going to be."
He said Cabinet made the decision it would not use a citizens assembly process for policy development.
This is largely because the decision is quite late in the process, Little said.
"So we won't be using that mechanism in terms of public engagement, we will have other ways of getting the public debate going."
Asked about a binding referendum on euthanasia, Little said that was a matter for Act Leader David Seymour and the select committee that is considering the euthanasia bill.
Seymour has a members bill on euthanasia currently going through the house.
"David has told me that he fully expects that there will be a referendum clause in that bill when it gets reported back."
Little said the Government is expecting there to be a referendum question on Seymour's legislation as well.
National Leader Simon Bridges suggested that the Government was attempting to distract from the general election itself, but said he didn't have a problem with the referendum being binding.
"I'm pretty cynical that you've got a Government here that wants to distract from the core issues of a general election," Bridges said.
He suspected two other discussed referendums would also be included on euthanasia and electoral reform, although Little has talked down those prospects.
Bridges would be voting against cannabis legalisation and said he hadn't smoked marijuana at any point in his life.