Mo’unga revealed he was made a serious offer to join the Warriors in 2018, the year he played the first of his 56 tests.
“It got as serious as meeting with Stephen Kearney, my agent, my father-in-law and ‘Sully’ [Warriors recruitment manager Peter O’Sullivan],” Mo’unga said.
“The reason I stayed was because I played rugby, and my only dream and goal was to be an All Black to play at a World Cup.
“It’s one of those things you’ll always have conversations with your mates, saying how it would have been awesome [to switch].”
Mo’unga began a three-season Japanese club contract after last year’s World Cup and helped lead the Toshiba Brave Lupus to the domestic title.
He is ineligible for the All Blacks until his contract ends and told the Sydney Morning Herald he is “working towards” representing New Zealand at the 2027 World Cup in Australia.
Mo’unga was in the crowd when the All Blacks beat England in the first test at Dunedin this month, their first match under new coach Scott Robertson.