However, it did show a campaign which focused on bread and butter issues for voters did work.
"It tells you a strong, disciplined campaign about real issues and things people care about has the best chance of success. You can't campaign on vacuous ideas like 'strong, stable leadership' or a manifesto that doesn't say anything."
He put the result down to a bad campaign by Conservative leader Theresa May promising "more of the same" compared to Labour's which offered something new.
"An unexpected number of Britons have gone 'we want something different' and that has affected Parliament in a completely unexpected way."
A spokeswoman for Prime Minister Bill English said he would not yet comment.
English met with May on his trip to the United Kingdom in January, describing her afterwards as "engaging," "a very determined woman and a clear thinker."
"I was left with the impression these are the kind of qualities you need, the UK needs, to get through what is going to be a complex process."
May had also promised New Zealand would be one of those first in line for a free trade agreement with the UK after the Brexit process and raised the possibility of a Commonwealth free trade region.
Other Labour MPs were also celebrating the result. Finance spokesman Grant Robertson tweeted that he was careful about drawing comparisons with New Zealand, but it did show big changes could happen during a campaign and showed the importance of an "authentic message".
He said he had not believed UK Labour would get such a result and was "delighted to be proved wrong."
Clare Curran tweeted that Labour had confounded the critics, adding that May should resign.
