Labour has promised to commit to the Children's Commissioner's target of reducing child poverty by 10 percent in a year.
Leader Andrew Little made the promise during an interview with The Nation on Saturday morning.
"We will have a child poverty measure that we're going to commit to, and I've already said every Budget we will report on how we're going against that measure, and we are absolutely determined to reduce child poverty in the way that the Children's Commissioner is talking about."
The National-led Government has refused to make any commitments, saying it has its own targets to meet.
"We're not taking on that particular one," Prime Minister Bill English told The Nation last weekend.
"We have a number of targets, many of which are quite challenging, that are coming in at all the angles on the issue of the welfare and future of our children."
Mr English's focus is on lifting incomes overall, because "everyone benefits from a growing economy".
His predecessor John Key also refused to commit to child poverty targets as defined by the Children's Commissioner.
Mr Little says according to the Commissioner's definition, there are around 150,000 children in poverty.
"Lowering that by 10 percent - I mean, yeah, if we can't do that and we're not prepared to commit to that - and I say we are - then, you know, we've got something seriously wrong going on."
A United Nations report in October 2016 suggested 300,000 Kiwi kids are living below the poverty line, and it's getting worse.
Amnesty International in February said one in three live in poverty, and 40,000 are hospitalised each year for preventable diseases linked to substandard healthcare access and housing.
Mr Little says Labour's targets will be "transparent" and reported on in every annual Budget.