"Here at the mission, we are seeing more and more families coming to us in desperate need, with children who are not being fed, clothed or housed adequately, and who are not receiving adequate medical care. The demand for food parcels alone has skyrocketed.
She said successive governments failed to address the growing problem, and the most recent National-led Government offered little assistance or funding.
"While successive governments have said they will do everything they can to address the issue, nothing much has changed. While they are talking and not acting, more and more children are going hungry, suffering from preventable third-world diseases and well on the way towards becoming dysfunctional adults."
Diane Robertson said thousands more children across the country would be condemned to living in poverty unless changes were made.
The Child Poverty Action Group called the documentary "compulsory viewing", labelling child poverty a moral and ethical issue.
"New Zealand has betrayed its proud history as a good place to bring up children. We should hang our collective heads in shame at our poor record for child health," the group said today.
Released just days before the general election, the documentary has ignited a political battle, with opposition parties hurling abuse at the National-led Government for not tackling the issue.
Labour deputy leader Annette King said the country cannot turn a blind eye to the urgent need of children any longer.
"Doing nothing is not an option. There are 200,000 children living below the poverty line in New Zealand. Many go without breakfast. They are living in cold, unheated homes."
She accused the National party of choosing politics over children, as she said the party hadn't prioritised child poverty.
