Labour leader Andrew Little has accused the Prime Minister of being "tasteless" after he suggested the Irish Examiner's tribute to Jonah Lomu shows the country needs a new flag.

Appearing on Paul Henry, Key used the front page as a prop in his argument for a fern on the new flag.

"Here's the silver fern, front page, with one frond coming off like a tear, with Jonah Lomu and his years," Key said.

Final five New Zealand flags: Which is your favourite? Share your stories, photos and videos. Contribute

"Amazingly powerful. That's New Zealand. Where was our flag? Nowhere."

READ MORE:

* Flying all five flags shows no bias

* 'Silver Fern' flag designer Kyle Lockwood: I would be 'honoured' to win

* First New Zealand flag referendum flaps into action

Little said there's no question the rest of the world associates the colour black and the silver fern with the All Blacks.

"That's why I suspect it was represented in that way at his funeral."

"I think it's pretty tasteless for the Prime Minister to use an occasion for mourning and grieving to press his case for particular design of the flag," he said.

Following his comment Kiwis have taken to social media to criticise the Prime Minister for using Lomu's passing as an excuse to promote his preferred flag.

Key disputed that and said "there will be people who support the silver fern used as a flag and they've been consistent in that view, certainly I have been".

"The point I was trying to make this morning is that that was the symbol that was used by the international media to reflect the loss of Jonah Lomu. I think the silver fern is an international symbol."

Key said the silver fern was a "more appropriate representation of New Zealand than what we've got".

The silver fern was known around the world, he said.

"That's the thing they use when we're doing well and when we're hurting. That's our flag," he told Paul Henry.

Henry said the country was "capable of handling several symbols".

"[The silver fern] is there now and it's a recognised symbol."

The pair agreed to disagree.

Little said Kiwis were seen everywhere at the Rugby World Cup final wearing black jerseys with silver ferns on them while draped in the New Zealand flag.

"I just don't think it's true to say that amongst great joy and great grief that it's the black flag or silver fern that people immediately this of, it's just not the case."

The 40-year-old former All Black died suddenly on Wednesday. Lomu was suffering from a chronic renal condition and is believed to have died of a blood clot in a lung.

The Irish Examiner was one of many papers around the world to mark Lomu's death.

The simple and poignant graphic was shared by hundreds of thousands of fans.