Prime Minister Chris Hipkins hs spoken to media about plans for 19 new marine protection areas for the Hauraki Gulf, nearly tripling the area covered.
The protections would include bans on bottom trawling and Danish seining in five areas, and increasing marine protections from covering 6 percent to 18 percent of the Gulf.
It would be put in place with a Bill introduced to Parliament - but not passed - before the October election.
Prime Minister Chris Hipkins announced the plan at Tamaki Yacht Club in Auckland on Wednesday morning, alongside Conservation Minister Willow-Jean Prime and Oceans and Fisheries Minister Rachel Brooking.
"The Hauraki Gulf - Tīkapa Moana - is an absolute treasure and needs to be protected for the enjoyment of future generations," Hipkins said. "We know action is needed now. Today's announcement follows years of careful work and extensive consultation, and strikes a good balance."
He said there were broader ongoing conversations about whether to ban bottom trawling, but "we'll deal with that everywhere rather than in isolation".
The Bill would be introduced into Parliament in the next few weeks, Hipkins said, and he expected it to pass early next year.
"Government continues to govern right through till election day, that's not new and of course we'll be backing this Bill all the way through."
Prime said some protection areas would be covered by a "high protection area" category, with strong restrictions while also recognising kaitiakitanga and other tangata whenua cultural practices.
"Marine reserves are something that we've had in legislation for some time, we only have a few of them around this area in particular. High protection areas are a new tool that we've come up with through the consultation process to strike a balance of marine protection but also the continuation of customary practices," she said.
"They both offer a high level of protection for the marine [environment] in that there won't be able to be commercial fishing or recreational fishing in those areas."
The new legislation would set up 12 such areas, along with five new seafloor areas to preserve seafloor habitats with bans on bottom-contact fishing methods.
It would also include an extension to the country's first marine reserve covering Cape Rodney to Okakari Point Marine Reserve (Goat Island) and Te Whanganui A Hei (Cathedral Cove) Marine Reserve on the Coromandel Peninsula.
"We've heard the community call for marine protection. Sustained action now is critical to ensuring we can continue to share stories of Hauraki's abundance," Prime said.
She said marine protection proposals announced at the end of last year had more than 7500 submissions.
Brooking said statutory processes meant further consultation would be needed on different options for the seafloor areas, continuing into September or October - so no final decisions would be made on that before the election.
"The changes proposed today in both portfolios, those are things that have come up from community and scientists and tangata whenua as we've heard about before. And they will definitely make an impact to the environment."
She said the legislation came alongside the Ministry for Primary Industries' Hauraki Gulf Fisheries Plan, which was the first to treat fish stocks on an ecosystem-wide approach rather than by species.
"Species like snapper, kingfish, and kahawai all live together in the Gulf, and are affected by local conditions, by the things humans do, and by environmental factors such as climate change," she said.
The plan took five years to come to fruition and would be reviewed annually, she said.
Prime said the application for a Marine Reserve around Waiheke was a separate process.
"As I am the decision-maker on that and I am yet to receive advice from my department around that decision, I can't comment on that today."
Greens urge further action to protect oceans, National cautiously supportive
The Green Party has long held a policy of phasing out harmful fishing practices in the Gulf, and banning bottom trawling on all seamounts - mountains under the sea.
In a statement, the party's Oceans and Fisheries spokesperson Eugenie Sage welcomed the announcement but urged the government to make it a first step of many.
"For decades, successive governments have allowed overfishing, sediment pollution, and destructive fishing practices to degrade the health of the Gulf, despite repeated calls and pressure from the community and mana whenua for change," she said.
"Our biggest disappointment is that this has come so late in the term. It is good to see a commitment to introduce legislation to establish these new protected areas, but very disappointing it won't become law before the election."
She said the Ministerial Advisory Committee on Sea Change had raised concerns about a lack of urgency three years ago, and the proposed legislation did not need to wait until the final weeks of the Parliamentary term.
"People want bottom trawling stopped to protect the seabed and the seafloor species. The time is now to make this happen. This is even more urgent when the biosecurity threat of Caulerpa seaweed is spread through trawling."
National Party leader Christopher Luxon said he had not seen the detail of the plan, and would need to look at that before commenting too deeply.
"But we do support anything that actually protects the Gulf, so first blush I sort of say we'd be open and supportive.
"Again, the devil will be in the detail and we know ... there's multiple stateholders and I'd want to understand that before commenting further."