03/03/2016 10:31 AM AEDT | Updated 15/07/2016 12:51 PM AEST

New Zealand Flag Referendum: Union Jack Or Silver Fern?

Hagen Hopkins via Getty Images
WELLINGTON, NEW ZEALAND - OCTOBER 12: Silver Fern (Black, White and Blue), by Kyle Lockwood, flies on top of the Wellington Town Hall on October 12, 2015 in Wellington, New Zealand. The Flag Consideration Panel has narrowed down to the five flags which will then go to referendum later this year. (Photo by Hagen Hopkins/Getty Images)

New Zealand's flag change debate will be decided as the final set of voting begins in a referendum on whether to change the national flag.

Voters will choose between the current Union Jack flag and the proposed Silver Fern flag, designed by Melbourne-based New Zealander, Kyle Lockwood.

New Zealand Prime Minister, John Key, is pushing for the flag change and said Kiwi's will regret the decision if they stick with the current flag.

"They'll wake up in a few months' time and they'll realise what a terrible mistake they made, because it's not going to make a blind bit of difference to me," Key told Radio New Zealand National.

"The point here isn't for me to get a flag I want. I'm simply one vote out of the millions of people who may potentially vote. The whole purpose of this was to give New Zealanders the chance to decide which flag they think represents them best going forward."

The Union Jack flag

The Silver Fern flag

The Flag Consideration Project started in May 2015 when a nationwide engagement program commenced to gather New Zealander's views and values in regards to alternative flag designs.

The first referendum -- running from 20 November to 11 December last year -- asked voters to rank five alternative flags. The Silver Fern was chosen as the preferred replacement, receiving 50.58 percent of the vote.

Voting in the final referendum will close on 24 March with the final result declared on 30 March.