Evangelical churches are accusing the Government of "religious treason" for promoting a statement that Christianity is no longer New Zealand's state religion.

At a national inter-faith forum opening in Hamilton tomorrow Destiny Church and the Vision Network of evangelical churches are preparing for battle against a draft national statement on religious diversity which says "New Zealand has no state religion".

Their objections threaten to prevent consensus at the forum and derail a plan for Prime Minister Helen Clark to present an agreed New Zealand statement to an Asia-Pacific inter-faith dialogue at Waitangi in May.

Philippines President Gloria Macapagal-Arroyo will attend the Waitangi meeting, returning Helen Clark's attendance at the dialogue in the Philippines last March. The Foreign Ministers of Australia and Indonesia have also been invited.

The draft statement, prepared for the Human Rights Commission by Professor Paul Morris of Victoria University, affirms long-standing principles of religious freedom, tolerance and a "national commitment to religious diversity".

Its first principle says: "New Zealand has no state religion. The state treats all faith communities and those who profess no religion equally before the law."

Another principle says: "Schools shall teach an understanding of the diversity of religious and spiritual traditions in an impartial manner."

The document is intended to be "aspirational" and would not have the force of law. But this weekend's Hamilton forum will include a presentation by a Nelson educationist, Rex Bloomfield, who is lobbying to have religious diversity included in the new school curriculum.

Destiny Church Bishop Brian Tamaki said the document was "dangerously ambiguous".

He said New Zealand's head of state, the Queen, was presented with a Bible at her coronation and told, "This is the royal law". She is the supreme governor of the Church of England and appoints its bishops on the advice of the British Prime Minister.

"That is the chosen religion of the Head of the Commonwealth. For us to depart from that, don't you think that that is bordering on creating some type of treason, religious treason anyhow?" Bishop Tamaki asked.

He said Christianity was also the religion of the first Maori King, Potatau, and was an integral part of the national anthem, God Defend New Zealand.

In addition, Christians still made up a majority of the New Zealand population - 51.2 per cent in the 2006 Census, although down from 60.8 per cent in 2001.

"It's the same story - a small group, a minority in government, is pushing another agenda through and the majority of people don't want it," Bishop Tamaki said.

"We don't deny people the right to come into our country with a different religion. All people are welcome to all religions, but they should understand that they are coming to a Christian nation where the national religion is being held as Christianity."

Vision Network director Glyn Carpenter, who represents evangelical churches on a working group co-ordinating the diversity statement, said the framework of a democratic state, including freedom of religion, came from a Christian tradition.

"We believe it is entirely appropriate for our Parliament to reference the Christian faith, as it still does, through a Christian prayer," he said.

He objected to requiring church schools to teach other religions, and said all schools should teach "the significance of the Christian faith for our nation and the type of society we have".

However, another member of the working group, Anglican Bishop Richard Randerson, said the evangelicals were confusing "the significant role of Christianity in the life of the country", which he supported, with being the official state religion, which it was not.

Bishop Randerson - who last month infuriated many conservative Christians by describing himself as an agnostic - said the Anglican Church in New Zealand was independent and elected its own bishops. The Queen did not have a role in the church here.

He believed church schools should have no difficulty in "educating people about the nature of the society in which we live, including the different cultures, which includes religious backgrounds of other people".

He did not believe the majority should impose rituals on others in public places such as Anzac Day ceremonies or Parliament.

Parliament's standing orders committee has since 2003 been considering a petition to remove references to Jesus from the daily parliamentary prayer.

* Clarification: Bishop Richard Randerson was referred to as an agnostic. However, he does not mean this in the commonly understood sense that nothing can be known of the existence of God but rather that the existence of God cannot be proved or disproved by scientific means.