The Government will today introduce the much-anticipated Zero Carbon legislation to Parliament, setting targets that could mean huge changes to New Zealand's agriculture sector.

It commits to what is called a "split target" – aiming to reduce all greenhouse gas emissions, aside from biogenic methane, to net zero by 2050.

Biogenic methane – the emissions created from livestock such as sheep and cattle – is not completely exempt as the bill commits to reducing it to 10 per cent below the 2017 levels by 2030.

To reach the target, some of the measures could include reducing the number of gas emitting animals and accepting technological developments to reduce emissions from animals.

The bill also commits to reducing gross emissions of biogenic methane to between 24-47 per cent below the 2017 levels, by 2050.

This range, however, is subject to a review by the Climate Change Commission in 2024 to take account of any future scientific developments.

The bill – officially called the Climate Change Response (Zero Carbon) Amendment Bill – does not set out how these targets will be achieved.

That is up to the Government.

Prime Minister Jacinda Ardern – who has referred to climate change as "our generation's nuclear-free moment" – said New Zealanders have made it clear they want "leadership and consensus" on climate change legislation.

Ardern said the bill was a "landmark" piece of legislation.

"New Zealanders have demanded it – and today we delivered it.

"We want to avoid the worse impacts of climate change."

Ardern said it would be "gross negligence" to let future generations take on the burden of climate change.

The Government was already taking steps to curb climate change, including planting 1 billion trees and halting any future offshore oil exploration.

Ardern said a practical consensus had been built "that creates a plan for the next 30 years, which provides the certainty industries need to get in front of this challenge", she said.

Carbon dioxide is the most important thing that needs to tackled, Ardern said – "that's why we've taken a net zero carbon approach".

Climate Change Minister James Shaw said climate change was the greatest challenge of all time. The bill gave New Zealand a plan to deliver on its Paris commitment to limit global warming to 1.5 degrees.

In fact, the bill makes it legally binding for New Zealand to achieve that objective.

He said New Zealand is well positioned to meet this objective.

"We have over 80 per cent renewable electricity generation and will have more by 2035."

As well as setting the greenhouse gas targets, the bill would see the establishment of an independent Climate Change Commission, tasked with providing the Government with expert advice.

The Commission will be made up of seven members.

The bill has been well thrashed out with the three governing parties – Labour, NZ First and the Greens.

The National Party has also been involved. Ardern thanked National for conducting the negotiations in good faith and for "setting politics aside".

The bill has been the subject of intense negotiations for months.

Based on the original estimates of the bill's progression through the Parliamentary system, the bill was mean to be introduced in to the House October last year and in force last month.

That timeframe was pushed back to and, according to the Ministry for the Environment, will now be coming into force late this year.

This is likely because any zero carbon legislation will be bipartisan and will have Opposition support, as well as that of the Government's.

In fact – according to Ardern's March diary – she, National's Climate Change spokesman Todd Muller, Leader Simon Bridges and Shaw met to discuss the bill early in the month.