Prime Minister Chris Hipkins says schools don't need National leader "Christopher Luxon's permission" to ban mobile phones.
Reacting to a new National Party policy which would see cell phones banned during class and breaks at primary, intermediate, and secondary schools, Hipkins said school leaders already have the ability to decide whether a ban is appropriate for their students.
"They don't need Christopher Luxon's permission to do that. Many schools do that already," Hipkins said on Wednesday.
"Parents who run schools' Board of Trustees are in the best position to make decisions for their school in terms of what is practically implementable and what the best option for their school is.
"Those schools that have banned cellphones, I have fully supported them previously as Minister of Education and as Prime Minister."
He said schools' Board of Trustees represent their parent communities so the decision should rest with them.
"They don't need central Government dictating to them what they should be doing and how they should be doing it."
The National Party's policy would allow schools to decide how to enforce the ban. It could mean students are required to hand in their phones when they arrive at school or leave them in their bags until the end of the school day.
"Parents can contact students via the school office, and exceptions for students with health conditions or special circumstances will be permitted," Luxon said.
The National leader said removing cell phones from schools would allow students to concentrate on learning.
"Students only have one shot at their school years, and we want to help them make the most of their valuable class time," Luxon said.
"Many schools and parents are concerned about the use of devices and research indicates there are health and social benefits to reducing screen time and encouraging students to interact with each other during their breaks."
A number of overseas jurisdictions already impose bans on mobile phones in schools, including in Australia. New South Wales, which has previously banned phones in primary schools, is extending the ban to secondary schools later this year to remove "unnecessary distractions".
Two weeks ago, the United Nations' education agency said technology, including smartphones, should only be used in schools if they have a clear role in supporting learning.
The UNESCO report said studies in Belgium, Spain, and the United Kingdom had found banning "mobile phones from schools improve academic performance, especially for low-performing students".
Luxon told AM on Wednesday morning that the ban had worked overseas.
"As you've seen in countries all around the world - you've seen all the Australian states do it just recently as well - is that the evidence is really clear," Luxon said. "Phones are a real distraction and a disturbance in the classroom and when they've been banned, actually, there's a big improvement in student achievement and outcomes.
"The research internationally… is really strong and particularly for low-achieving learners, there's a really big step-up and improvement without the distraction and disturbance of the phone going off all the time."
But Papatoetoe High School principal and President of the Secondary Principals' Association Vaughan Couillault told AM that cell phones can be integrated into school work.
"On the surface of it, it sounds like a way to address an issue the world is facing in terms of screen time and distraction but when you dig down into the stuff at the bottom of the announcement, you see it's no different to what's actually already happening in schools and classrooms anyway," he said.
"We don't necessarily need centralised control and governance over this because schools are already enacting their own policies and putting their own systems and procedures in place to do pretty much exactly what's already on the bottom of that page."