The Greens have again called for rent controls after data out on Tuesday showed median rents across Aotearoa hit an all-time high of $650 a week in the year to March.
But ACT has hit back, calling the party "economically illiterate" and instead advocating for removing regulations.
Trade Me's latest data showed national median weekly rents rose about $50 in the past 12 months (or 8.3 percent), which is "unusual", according to property sales director Gavin Lloyd.
Apartments also reached a record high of $525 a week across New Zealand.
Green Party housing spokesperson Tamatha Paul said on Tuesday that landlords are the only people being "well-served" by the Coalition Government's policies.
"People who rent are already struggling with sky-high rents – and can see very clearly the lie that tax cuts for landlords will trickle down to help," Paul said.
She said the Government gave landlords a "$2.9 billion tax break" while others struggle and rents have never been higher.
"Landlords are laughing their way to the bank," she added.
Trade Me data showed the biggest median rent increase of 10 percent was in the Manawatū-Whanganui region, now at $550. The Wellington/Pōneke region was unchanged overall at $650.
If renting is to be attractive and affordable, Paul said New Zealand needs controls on rent increases, a rental warrant of fitness, and to rapidly build new housing.
"Housing is a human right. We can and must ensure it is afforded to all," she said.
Paul also said the Government has the power to regulate the rental market to put people before profits, rather than treating housing like a business.
"The main driver for the increase in rents is the ability of property speculators to drive up house prices and landlords to lift their rents at will, to suggest it is anything else is merely a distraction from the core issue."
But ACT's housing spokesperson Cameron Luxton said the Greens' call for rent controls are "economically illiterate".
"One economist famously described rent controls as the most effective way to destroy a city short of bombing it," Luxton said.
"When property owners aren't allowed to charge a full market rate, investors aren't willing to invest in new rental units and landlords lose the incentive and financial resources to properly maintain their properties."
There would be a "dire shortage of rentals" if a warrant of fitness was introduced and tax deductibility for landlords was removed again, Luxton argued.
He said that red tape preventing homebuilding should instead be removed.
