National leader Christopher Luxon is defending his party's policies aimed at reducing rents despite not being able to reveal what impact they would actually have.
National has relentlessly attacked the Government over the increasing cost of living, specifically for renters.
The party has blamed Labour's extension to the Brightline test - which doubled the length of time investors must own a property to avoid paying tax when they sell - and removal of interest deductibility - which allowed interest payments to be offset against income - as reasons for the cost of rent increasing.
Luxon has committed to removing the Brightline test extension and reintroducing interest deductibility on rental properties to reduce rents.
But when questioned on AM how much rents would actually drop as a result, Luxon said he couldn't say.
"I can't tell you that, but what I can tell you is that we have to work much harder at getting rent down and it's about rental supply and a whole bunch of things," Luxon told AM.
"What I am saying to you is that the essentials across New Zealand, whether it's power, food rent, everything is going up and through the roof and it's because the Government has let inflation take root in this economy."
When pushed on how much his policies would reduce rents, Luxon doubled down saying he "couldn't" say.
"All I am saying to you is there are a number of things we could be doing to improve rent, and there's a number of things we could be doing to improve homeownership, as there are a number of things we should be doing to improve social and state housing as well."
AM co-host Ryan Bridge then questioned whether Luxon had actually had the policies checked by an expert and whether they had any prediction over how much it would help.
"People at home will be wanting to know quite specifically from you, because they've heard a lot from governments of all different colours, they will be wanting to know quite specifically," he said.
Bridge then asked how much National's interest deductibility rules alone would shave off rents. But Luxon wouldn't answer that either.
"What I can tell you is that since those interest deductibility rules were removed, since the Brightline was extended from two years to 10 years we've seen an increase in just one year of $50 per week in rent. "
Bridge then asked whether National was saying removing those rules would reduce rents by $50 a week, but Luxon said he couldn't say.
"The officials gave the Government the same advice they said, 'Look if you do those things it's going to lead to higher rents for renters' and that's a challenge and that's the rationale for why we think if you remove those things that's something you can do."
But he wouldn't say how much rents would drop if those rules were removed, saying they are just one aspect of many areas that need work.
"There's a series of actions, there's not enough happening. You've actually got to be able to work each of the components of the housing crisis that we have.
"On rents as I've said you would work over the tax pieces because those costs are just getting passed straight to renters and it's also leading to a lower level of supply of houses and rental properties."
He also suggested encouraging developers to build rent to own properties could help.
Earlier in the interview, Luxon said Kiwis spinning around 35 to 40 percent of their income on rent was reasonable.
"A lot of people would say it needs to be around 35 percent to 40 percent living cost as a proportion of total income. But the reality is that it's different for different circumstances in terms of how other people manage their own finances.
"I am just saying when you've looked at historical banking assessments that's what people have sort of looked at. Anywhere from 30 to 40 percent around the world seems to be reasonable," he said
Currently 1.4 million Kiwis rent with 25 percent spending around 40 percent of their income on rent - the second highest in the world behind just the UK.
When Bridge pointed out 40 percent was actually quite high given that leaves just 60 percent for all other essential costs such as power, food, and transport. Luxon hit back saying it was only difficult because the cost of everything else was going up.
The Government has recently admitted the increasing cost of living is a crisis and slashed fuel taxes by 25 cents a litre to combat increasing petrol costs. It also comes as other Government measures previously announced are set to kick in, such as an increase to the benefit, minimum wage and Family Tax Credits in April, and the Winter Energy Payment in May.
Finance Minister Grant Roberton has heavily criticised National's overall economic plan, saying it "would leave New Zealanders worse off".