Hundreds of people on Monday set out on a nine-day march to New Zealand's capital of Wellington in protest over legislation that would reinterpret a treaty at the heart of race relations in the Pacific country.

Convoys of cars and marchers set off after a dawn ceremony at Cape Reinga, in the country's far north, and will stage rallies in towns and cities as they move south, according to Eru Kapa Kingi, spokesperson for Toitu Te Tiriti or Honour the Treaty.

While the march, or hikoi, was sparked by the bill currently before parliament, organizers want the march to ignite a broader conversation about New Zealand's relationship to Maori, he said.

"This is to build a hunger not just with Maori but also people in Aotearoa (New Zealand) to properly understand the people of this country and what happened to Indigenous people," he said.

The Treaty of Waitangi, first signed in 1840 between the British Crown and more than 500 Maori chiefs, lays down how the two parties agreed to govern. The interpretation of clauses in this document guides legislation and policy today.

Introduced by New Zealand's centre-right government last week, the Treaty Principles Bill, would enshrine a narrower interpretation of the treaty in law. Decades of interpretation by the courts and a separate Maori tribunal have tended to expand Maori rights and privileges.

Associate Justice Minister David Seymour said last week the bill would allow the important political and constitutional questions raised by the treaty to be decided in parliament instead of the courts.

His ACT New Zealand party won 8.6% of the vote in last year's election and argues non-Indigenous citizens are disadvantaged by policies designed to uplift Maori, who are over-represented in many measures of social and financial disadvantage.

While the bill will almost certainly fail, its introduction has inflamed racial tensions in New Zealand where Maori make up about 20% of the country's 5.3 million people.

The protest will hold a large rally in New Zealand's largest city Auckland on Wednesday before traveling down the country to reach Wellington next Thursday. Organizers expect tens of thousands of protesters to participate by the time it gets to Wellington.