Education Minister Anne Tolley says she will sack the boards of primary schools which allow teachers to boycott national standards, saying they would be refusing to obey the law.

Tensions over the new standards in literacy and numeracy are increasing.

Teachers' and principals' unions are lobbying school boards to support them in their call for a trial period before the standards are introduced nationwide.

The unions have also threatened boycotts and industrial action, and last week wrote to principals urging them to ask school boards to voice the same concerns.

Mrs Tolley has ruled out a trial, and said that in "extreme" cases of a boycott she would dissolve the board involved - because the trustees would be refusing to obey the law - and replace it with a commissioner.

"If despite having that pointed out to them, they absolutely refused, I do have the power to dissolve the board and put in a commissioner," she said.

"In the end, I would have to do that. I don't think it would come to that, but if it went to the nth degree I would do it. You just cannot have schools disobeying the law."

Mrs Tolley said the Ministry of Education would give as much support as possible to boards stuck in a standoff with teachers.

But she would not be backing down on her decision to introduce standards nationwide from next year.

The minister said she had already made many changes in response to concerns from the unions but each time, they had returned with more and she believed their arguments were now purely philosophical.

"That's why I'm putting my foot down ... If there are changes needed, we will make them.

"I'm not saying this is it from day one. But we have to get started because this is about kids failing in the system. I'll do whatever it takes to make this work."

Labour's education spokesman, Trevor Mallard, said Mrs Tolley was transferring her battle against academics and teachers to school boards.

"I'm surprised she's putting herself into that corner. She does have a choice. She can take a tiny step backwards and trial the system to get evidence that it's better than the systems already available."

Auckland University education head Professor John Hattie and three other education academics have made a joint call for a trial, saying a hasty implementation could result in failure of the policy.

Frances Nelson, president of the NZ Educational Institute, which represents primary school teachers, said she was disappointed at Mrs Tolley's refusal to back down.

"The way she is approaching it is like she's got herself into a corner and can't find a way out without losing face."

The School Trustees Association broadly supports national standards and its president, Lorraine Kerr, told the Principals' Federation and the NZEI they were being "irresponsible and unprofessional" in telling principals to lobby their boards.

A meeting of 80 Northland principals last week unanimously agreed not to implement the standards until their effect was better known.