A service providing independent advocacy for children in state care has launched alongside the new Ministry for Vulnerable Children.

Voyce - Whakarongo Ma, launching this afternoon, is the first such service in New Zealand.

While its phone and online advocacy service is expected to start later in the year, with a face-to-face service scheduled to kick off in 2018, organisers say the non-government organisation will start small by building relationships with children in care.

"Children and young people fundamentally deserve to connect with each other and be listened to, and New Zealand's care system has been crying out for a service like this for many years," said Tracie Shipton, director of Dingwall Trust - one of the key members behind the service.

The service is a joint project between four philanthropic organisations and two NGOs, with the government chipping in $1.2 million to set up the programme and another $6.9 million for its expansion over the next four years.

While independent of the Ministry for Vulnerable Children, opened on Friday, Voyce will work closely with the ministry to provide advice, Minister for Children Alfred Ngaro said.

It also aims to connect young people in care through events and community activities.

Children's advocate and Voyce board member Tupua Urlich, 21 - who was put in state care at age five - said he hoped the service would help connect children to their culture and roots.

"Connection and culture is just so vital to children and young people, and is something that a lot of kids in care miss out on growing up, myself included, which is why I am so optimistic about the service and its promise to our tamariki," he said.

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