One of the country's leading philanthropists says taxing the rich to narrow the income gap would be unfair because the country is overtaxed as it is.
Dame Rosie Horton says increasing the rate on the wealthy to provide services for lower income New Zealanders would just discourage hard work.
National and Labour have been arguing over whether income inequality is reducing or worsening and the best way to tackle poverty.
Equality advocates say the top 20% of income earners in New Zealand are almost eight times as wealthy as the poorest 20%, and that gap has led to high rates of things like mental illness and violence.
One proposal to bridge the gap is a 45% tax rate on the wealthiest income earners.
But Dame Rosie says the country is already overtaxed and demanding an even greater take from the wealthy would only put people off working hard.
Dame Rosie says many of her wealthy friends are very philanthropic but give quietly so people are unaware of their generosity.