National leader Simon Bridges said Asia was the most important region for New Zealand and peace on the Korean Peninsula would bolster that. "So while we are a small player we share a very large stake in the success of the talks."
He said the symbolism of the meeting was "incredibly powerful" and Trump will have proven many of his detractors wrong if the meeting secured a breakthough.
"Whilst in a sense it is deeply symbolic and not much more than that at the moment you couldn't have lasting peace without such a meeting. Actually, if Trump can achieve that or get the region on the path to that, he's done a heck of a lot more than his detractors thought he would.
"It was unthinkable just a few months ago so to have them in the same room, clearly comfortable in each others' company, was in itself a remarkable achievement."
Act leader David Seymour said if Trump could redeem a long-standing problem, credit should be given where it was due.
Green Party Foreign Affairs spokeswoman Golriz Ghahraman said peace and reunification had long been sought by the people of Korea and recent developments reflected the grassroots efforts of the Korean people.
In a statement that did not mention either Kim or Trump directly, she said it was an exciting day for peace.
"While there are very few details about how denuclearisation will happen or how the United States will provide for North Korea's security, both promises are a welcome shift in focus on the well being of the people of the region."
Massey University senior lecturer in security studies Dr Mark Lanteigne told Newstalk ZB's Heather du Plessis-Allan that the fact the contents of the agreement were not immediately revealed was "a bit of theatre".
"It is part of a step-by-step process. This is not the final phase of negotiations."
The meeting so far had been a win for the North Korea Government, which had its flag beside the United States' as well as a lot of positive photo opportunities, Lanteigne said.