Labour leader David Shearer said National's "tweaks" to KiwiSaver would be little consolation to the thousands of would-be home owners searching this weekend's property pages for an affordable home.
"National needs to address the two major drivers of house prices - the shortage of affordable homes and speculators. It's time to stop dancing around the problem and offer some real solutions. First home buyers need affordable options," he said.
The Greens said National's policy did nothing to address New Zealand's wider housing affordability crisis.
"Chucking a bit of cash at first home buyers with access to fund a deposit will assist some first home buyers but house prices will continue to rise and many more New Zealanders will be left with no means of ever affording a house," co-leader Russel Norman said.
The changes to the Welcome Home Loan scheme would actually stop many low and middle income New Zealanders from ever owning a home, he said.
"National's failure to increase the supply of affordable social housing and its failure to constrain foreign buyers of residential housing and introduce a capital gains tax on investment properties has led to a renewed housing bubble."