New Zealand's legal cannabis future could be a while away

As New Zealand moves towards the legalisation of medicinal cannabis many, turn are wondering if the Government may eventually decriminalise cannabis for recreational use.

The Green Party secured a promise of a referendum on the personal use of cannabis as part of their Confidence and Supply Agreement with Labour - that's looking likely for 2020.

However even with a possible date for the referendum, it still could be some time before New Zealand joins the 31 other countries who have decriminalised.

Former Associate Minister of Health Peter Dunne broke down how long the process could take on Tuesday for Three's The Project - and it's not good news for those in favour of legalisation.

"The 2020 referendum offers a way forward on the one hand, but on the other it actually means the Government will feel no need to do anything before 2020," he said.

"So if people push for change in the meantime, they'll be told there's a referendum in 2020.

"If that votes yes then it will probably take the next three years to implement the sort of environment you'd need because you can't just have 'cannabis is legal, no rules'.

"You could end up with change being delayed another four or five years."

Watch the video for the full The Project interview.