Decision to step aside for Ardern has been vindicated, says Little

In June Andrew Little was in Whanganui announcing Labour's plans to put $3 million into repairing the north and south moles.

But such has been the political upheaval this month he was back in town on Tuesday, as a list only MP, and tossing the big questions up the chain.

Like would Labour support the Greens' proposal for a marine mammal sanctuary off the Whanganui and South Taranaki coast?

"I can't speak on behalf of the party, I'm not the leader anymore," Mr Little said.

"We've got Jacinda, and we've got our portfolio spokespeople who will talk about that sort of stuff."

Mr Little said the transition after handing over the leadership reins to Jacinda Ardern on August 1 had taken some getting used to.

"There's an emotional bump you have to get over," he said.

"It's a change for me and a change of pace as well. I was used to going absolute gangbusters at things, so it's a little easier."

But the decision was the right thing to do, he said.

"The poll results since absolutely vindicate that, for sure.

"It's great to see what Jacinda has been able to do. It would've been nice if I was able to do that, but it wasn't happening for me."

Mr Little said he knew the party was capable of polling in the mid-30s but they were doing better than he expected.

"The sense I got was there was a mood for change," he said. "I obviously wasn't able to capture that."

"Jacinda has been able to very quickly and, sort of unfettered by baggage three years previously, she's gone in there fresh-faced and with energy and vigour."

Meanwhile, Mr Little said whether Labour would support the Greens' proposed marine sanctuary, in place of seabed mining, would be discussed after the election.

"I know a bit about the issue because I was involved in it closely when I was campaigning in New Plymouth," he said.

"We take that environmental stuff more seriously that what we did back 10 years ago.

"We've got to get that equation right that economic development shouldn't be running counter to the environment, it's got to be complementary to it".