The Aotearoa-New Zealand government is intent on passing new legislation that may exclude Māori tribes from Traditional coastal claims on title rights.

Māori activists are staunchly fighting the proposed bill, delivering a petition to the steps of parliament containing nearly 20,000 signatures from across the North Island.

The coalition government comprised of the National, ACT New Zealand, and New Zealand First parties want to amend a section of the Marine and Coastal Area Act to tighten up test cases against Māori groups winning Aotearoan customary marine titles.

The conservative government says it wants to restore the legislation to its "original intent" dating back to the 19th century.

Justice Minister Paul Goldsmith said cabinet will consider the petition, but the government aims to push through the legislation as early as next week.

The Tatutai Moana (Marine and Coastal Area) Customary Marine Title amendment bill that has passed its second reading this week has been condemned by former ministers on both sides of New Zealand politics, lawyers and also prominent iwi leader Aperahama Edwards, who said the bill was tantamount to a "raupatu", confiscation without any right.

The push to prevent the legislation pass through the country's unicameral parliament has been driven by activist Rueben Taipari and his group of supporters.

Speaking from the backdrop of the parliament on Thursday, Mr Taipari said the amendments were a greater threat than previous legislative changes with similar aims.

"It's worse actually because it's blatant," Mr Taipari said.

"When they did it in 2004, it was a negative reaction...a reaction to what they thought was going to happen.

"Twenty years later, we've shown that it's never been the case, we have never stopped access to the foreshore.

"What we have done though is we have created our mana again - we have brought back that management of kaitiakitanga, doing rāhui, doing mātaitai, rohe moana."

Mr Taipari travelled the length of the North Island from his home hundreds of kilometres north of Auckland down to Wellington over several days to gather more signatures and raise awareness of the proposed changes.

He said the chief purpose of a petition, which may not change the mind of the government, who hold 68 seats of the 123-seat House of Representatives, was an "exercise" to get Māori people talking.

"Actually, the petition was for us," Mr Taipari said.

"The different hapū that we have talked to have gone back to their communities, and they are putting together hui to discuss how they're going to defend themselves."

Opposition MPs from the Labour, Green and the Te Pāti Māori parties greeted Mr Taipari for a pōwhiri - a cultural practice deeply rooted in Māori mythology - that serves the purpose of spiritually clearing a path to meet in a productive way amid a formal parliamentary handover.

But no members of the government from the three parties turned up.

Mr Taipari believed the changes were being pushed by "rich guys" supporting the government.

The Māori activist said all he possessed is love in his heart, spirit in his soul and a life force from his ancestors.

"Don't ask me, I'm just a poor guy," he told one of the reporters.

"I don't even have a car to get home.

"But I've just come down here to bring my aroha, my wairua and the mauri of my tūpuna."

Former Labour minister Willie Jackson, a Ngāti Maniapoto and Ngāti Porou Māori man, said the government just "changes the rules as it suits them".

"It's another shocking example of this government's attack on Māori," he said

"We're tired of the attack on Māori rights."

Te Pāti Māori MP, Tākuta Ferris, is calling on New Zealand/Aotearoa Governor-General Dame Cindy Kiro, the first Māori woman and the third person of Māori ancestry to hold the office, to prevent the bill from becoming law, should it pass its third reading.

"Her signature is the signature that will move this thing into law." he said.

"She's been challenged a number of times over the last two years to prevent that, in particular instances - hasn't done it yet - she should get her hands into looking after her people, lest the country be ripped apart by division."