A leading clothing designer has slammed a Ministry of Education proposal to introduce gender neutral uniforms to New Zealand schools, calling it a "time-wasting idea".

A group of school pupils in uniform

The Ministry is advising schools to offer gender-neutral uniforms to better provide for sexual diversity among students, as part of new guidelines released yesterday

The guidelines include provisions on "being inclusive and valuing diversity", in particular saying that school uniforms can reinforce gender norms, and encouraging schools to consider offering gender-neutral clothing choices for uniforms.

However, Denise L'Estrange-Corbet told ONE News that "gender neutral" was a difficult concept to define.

"All I can think of is that they're thinking girls should be wearing trousers but if it's gender neutral, shouldn't boys be wearing skirts?", she said.

Ms L'Estrange-Corbet believed time and money could be better invested elsewhere.

"I don't think it should have any more discussion - put more money into the education services and don't worry what the uniforms are".

The new guidelines also encourage schools to reconsider their toilet facilities to ensure pupils of all gender identities had safe spaces, saying "toilets can be unsafe environments for students who do not conform to gender norms".

Same-sex partners should be allowed to attend invite-type events such as school balls and sports coaches needed to understand gender identity and be vigilant for homophobia and other signs of discrimination.

Other guides in the document warn teachers that students must be educated about the harm of photographing others in a sexualised way.