The Government is throwing the kitchen sink at the coronavirus economic shock, pumping billions of dollars into keeping people in work, paying those who need to stay home, business tax cuts and benefit boosts.

A gigantic wage subsidy to keep Kiwis in work is at the centre of the huge $12.1b economic response to the coronavirus pandemic, the biggest peacetime government spend in history.

New Zealand Parliament Finance Minister Grant Robertson unveils $12.1b package to help protect the economy against the coronavirus fallout.

The $5.1b wage subsidy means any business losing serious income because of the pandemic will be able to pay fulltime workers $585 a week.

The Government will also pay people to stay home from work and self-isolate if needed - including contractors - and pump $500m into the health system.

To keep the economy primed, all beneficiaries will receive a substantial boost, with a permanent $25 extra a week for main benefits. It will also double the Winter Energy Payment for main beneficiaries and superannuitants in 2020 - making it worth $900 for singles and $1400 for couples.

Ross Giblin/Stuff Finance Minister Grant Robertson after presenting the package.

Finance Minister Grant Robertson unveiled the plan - worth a whopping 4 per cent of GDP - warning that New Zealand was heading into a recession that would likely be worse than the 2008 Global Financial Crisis.

"We hope to save some jobs with this package, but we will not be able to save all jobs," Robertson said.

"We cannot make promises that we can save every job or every business."

Relative to the size of New Zealand's economy it is larger than the recovery packages introduced in Australia, the United Kingdom, and Singapore, and larger than all the operating spend introduced by the Labour-led Government so far this term.

Prime Minister Jacinda Ardern said it was the largest peacetime government spend in New Zealand's history.

As tourist numbers dry up because of the weekend's sweeping travel restrictions and as stockmarket take a hammering, the Government is keen to keep the slowdown from becoming a shutdown.

ROSS GIBLIN/STUFF Prime Minister Jacinda Ardern said the package was just the start.

The wage subsidy scheme will see the Government pay employers up to $150,000 per business over the next 12 weeks to keep employees on. This will pay up to $585 per full-time worker and $385 per part-time employee. Any business that can show a 30 per cent decline in revenue for any month between January and June, when compared with the same month last year, will be eligible. It is available from Tuesday.

The $150,000 cutoff is equivalent to around 24 fulltime staff.

A new sick leave scheme will see the same amount of cash be made available for any workers or contractors who need to self-isolate for the required 14 days because of coronavirus. It will also pay out the entire sickness period for anyone infected with Covid-19. This is expected to cost $126m and apply to about 27,000 people - but this number is not much better than a rough guess.

ROSS GIBLIN/STUFF Finance Minsiter Grant Robertson said not every job would be able to be saved.

Eligibility for this new sick leave scheme is not available for those who are able to work from home. Employers are still expected to meet normal sick leave and employment law obligations.

A $2.8b package of tax changes will also be introduced for business - with interest waived for some late tax payments, more deductions for low value assets, deprecation deductions for commercial and industrial buildings, and a higher provisional tax threshold.

But it is not just small businesses and workers who will see cash, as the Government is keen to grow demand across the economy with another $2.8b going to beneficiaries and superannuitants.

Collette Devlin/Stuff Speaking ahead of the the Government’s economic response to the global COVID-19 pandemic, Finance Minister Grant Robertson said New Zealand was “well and truly” in recession planning.

The Government is permanently raising main benefits by $25 a week - meaning almost all benefits other than superannuitants will see a weekly boost.

"We know that those on low incomes and benefits spend the money they get. There is a stimulatory effect to that. And we know that more people may end up on the benefit," Robertson said.

The Government is also doubling the Winter Energy Payment for 2020, which goes to beneficiaries as well as superannuitants. These payments will double to $900 for singles and $1400 for couples.

Henry Cooke/Stuff Prime Minister Jacinda Ardern is confident New Zealand has the capacity to test more coronavirus samples.

Robertson said the Winter Energy Payment was the best way to get money to the elderly who he thought would need help.

The hours test will also be removed from the In Work Tax Credit - meaning people on benefits will be able to work more hours without seeing their benefits cut.

A further $500m will be pumped into the health system to increase intensive care support, and $600m will go into the aviation sector, who have been hard-hit by Covid-19. This will help keep air routes open.

Robertson emphasised that this package was "just the start" of the Government's response, with this year's Budget being recast as "recovery Budget".

In a speech to the House introducing the package Robertson emphasised his faith in Keynesian-style stimulus, as the first Labour Government introduced.

"In New Zealand we have been here before with major economic and social crises. In my lifetime we have seen governments respond with austerity and ideology that has done enormous damage to the fabric of our society," Robertson said.

"But we also have other examples such as the first Labour Government who responded with investment, pragmatism, optimism and kindness. It is from them that I take my lesson on how we recover and rebuild in a just, fair and far-sighted manner."

SIMON BRIDGES CRITICAL

National leader Simon Bridges said the package was needed but was sharply critical of its design.

"This shows your confused and your muddled priorities as finance minister," Bridges said to Robertson.

Collette Devlin/Stuff National Party leader Simon Bridges said the Government's Covid-19 package was full of confused priorities and he would have been more aggressive with job support.

"How much does health get? Half a billion dollars...It's too little late. And that's because you have prioritised other things."

He said money was "flowing faster" into the hands of beneficaries than workers and businesses.

Bridges believed that the $150,000 cutoff for the wage subsidies - equivalent to about 24 fulltime staff - was too small as many businesses larger than that would need help.

"There's a tourism business just outside of Tauranga; it runs a great operation. He has 40 staff," Bridges said.

"He is laying workers off right now—and your package, Grant Robertson, doesn't cover his workers."

"This is a situation where I got an email from wool exporters about 30 workers; they've gone to a four-day week. This package does not fully cover them."