Watch: John Tamihere and Phil Goff face off in a debate.

Watch: John Tamihere and Phil Goff face off in a debate. Credit: Pub Politics

John Tamihere shocked the audience at an Auckland mayoral debate by responding to his opponent's praise for diversity with a Nazi slogan.

On Tuesday evening, Tamihere and Phil Goff took part in a debate in Ponsonby's Chapel Bar during which they discussed transport, infrastructure and other topics.

Near the end of the event both candidates were asked to answer the question 'What do you wish for the grandchildren of Auckland?'

Phil Goff said he wanted them to grow up in an inclusive, diverse city, and called back to an earlier question over his decision to bar Stefan Molyneux and Lauren Southern from speaking in Council-owned venues.

"We won't put up with the sort of nonsense we get from racists coming into this country to tell us that multiculturalism doesn't work."

He said his soon-to-be-born grandson, who is of mixed-race parentage, will represent the future of Auckland.

"Well I say Sieg Heil to that," John Tamihere replied.

"Like the Nazis?" Goff said. "What do you mean by that? That's weird."

"I've never heard such a prepared speech delivered so boringly," Tamihere continued, chuckling.

The comment can be heard at 1:18:53 in the video below.