National would undo or restrict major components of the government's families package, leader Simon Bridges says.
The package giving thousands of low- and middle-income families extra money came into force at the weekend.
Watch National Party leader Simon Bridges speaking with Guyon Espiner on Morning Report:
The package will cost $5.53 billion over the next five years, and National's promised tax cuts were scrapped to pay for it.
National argues those tax cuts would have helped more people than the families package.
Leader Simon Bridges said it was helping a relatively small number of families.
"There are many more families who are not receiving it and I would argue are worse off because they're not getting the tax relief that we were putting into place."
Mr Bridges said his party supported the changes to paid parental leave but not the baby bonus and the winter housing payments.
He was not saying the baby bonus would go entirely, or how it might be changed, but favoured a more targeted approach.
The winter payment would also be more targeted to those who needed it, he said.
Social Development Minister Carmel Sepuloni said 64,000 children would be lifted out of poverty which was more than under National's package.
The government was committed to doing as much as it could to reduce child poverty.
Mr Bridges said some people would not require the winter energy payments offered to beneficiaries and superannuants but "people were not going to do that".
But Ms Sepuloni said by the end of June 1337 people had opted out of the winter energy payment - all except one superannuitants or veterans.
What's included in the package:
- Paid parental leave will jump from 18 to 22 weeks and to 26 weeks from July 2020
- The Winter Energy Payment will be introduced giving most beneficiaries and all pensioners an additional $15-$20 a week during the colder months
- Parents of babies born from 1 July will receive up to $60 more a week after the first year, for the second and third years, support will continue for middle and low-income families
- Reinstatement of the Independent Earner Tax Credit, which provides income support for low and middle-income earners who do not benefit from Working for Families tax credits
- The rates of Orphan's Benefit, Unsupported Child's Benefit and Foster Care Allowance will increase by $20.31 a week