Iwi leaders say dealing with Oranga Tamariki is difficult and frustrating and it's going to take huge improvements before a partnership between them will work.
From next month, new legislation will require the Children's Ministry to work with Māori, but several iwi say the agency overrides them, withholds information and is inflexible.
When Ngāti Ruanui found out three young descendants were living in a hotel in Auckland and needed care, the South Taranaki iwi mobilised to find caregivers with whakapapa links.
But chief executive Debbie Ngarewa Packer said Oranga Tamariki went against their wishes to keep the kids together, and sent only one child to them.
"Even though they knew that there was this iwi relationship going on and this was a test run for us to try and show how we could make it work, there were no extra efforts," she said.
"There were no favours, don't get me wrong - nothing that changes the dialogue just because there is a whole iwi waiting at the other end."
Ms Ngarewa Packer said while the agency's Māori unit is good to work with, there are concerns that the agency withholds information, will not return their calls and misses deadlines.
"In my life, I have never seen anything so exasperating and so ridiculously archaic.That is why mistakes are happening there.. Because the left hand cannot talk to the right hand."
Ngāi Te Rangi chief executive Paora Stanley said he shed a tear when the Tauranga iwi closed its care and protection services in 2016, after 15 years.
But he said the child welfare agency did not resource them properly and audited them so often, that they felt driven out of the work.
"There is still a lot of control that the state has on that and the state wields that power quite well," he said.
Mr Stanley said it was important to note that Oranga Tamariki is not the one abusing children, but said they were unflexible and arrogant when it came to working with Māori.
"They are in themselves a difficult organisation to deal with. Depending on who you go to in management, they are not always forthcoming with information or forthcoming with support and help.
"When you speak to other Māori leaders across the country who work in this space, they often find them quite difficult."
Whanganui kaumātua John Maihi said it is nothing new. He said the former Tupoho Iwi and Community Services Trust ended some of its child welfare services 20 years ago because of road blocks.
"We could not get past the senior social worker, she had the mana to stop everything. In the end, we were not even bothered with the thing," he said.
He said iwi are keen to offer solutions to reduce disparities for Māori in state care, but he is not confident that a relationship with the agency will work.
"Not the way that things are going at the present moment - they are not good.
"The idea of us looking into doing it, as long it is how we believe it should be done, then it is worth looking into."
Ngāti Kahungunu is helping Oranga Tamariki investigate its controversial attempt to remove a Māori newborn from its mother in Hawkes' Bay hospital after slamming the agency for its process.
Come 1 July, Oranga Tamariki's new legislation means it must partner with iwi and devolve its resources.
Ngāpuhi iwi leader Sonny Tau said it has an agreement in place with Oranga Tamariki but the agency has acted outside of that agreement before.
He said the most important thing is the safety of children and acknowledges the difficult role the agency has, but he said they acted as if they always knew best.
"We want to develop a process and a solution to our tamariki with Oranga Tamariki which we are working through now," he said.
"But we need the resourcing and the will from Oranga Tamariki to do that."
Te Rarawa iwi leader Haami Piripi said iwi have the connections to whakapapa and the expertise in strengthening culture, and it is vital that their solutions are taken seriously.
He said Children's Minister Tracey Martin's heart is in the right place and he is hopeful about the tribe's future relationships with the agency.
"It has been an improving one but it has got to get a lot, lot better," he said.
"I think the introduction of our people, our methodologies, our models and out networks will make it better."
In a statement, Oranga Tamariki said building partnerships with iwi is one of its core priorities and last year it introduced a framework for cultural competency that applies to all staff.
The agency has already begun formalising relationships with iwi, including co-design agreements signed with Ngai Tahu, Waikato-Tainui and Ngāpuhi.
"We're keen to be partnering and working with all other iwi around the motu, but we must be respectful and wait for when timing is right for them also," it said.
"We've been inviting proposals of all Iwi on their approaches to best support and care for their tamariki within their iwi rohe.
"Ultimately we'll be guided by the readiness of all iwi to engage us, because it's vital that we to get all partnerships right."
However, Mr Stanley said iwi can make change outside of Oranga Tamariki - the Tauranga iwi is currently running preventative measures within its own rohe.