It is "inevitable" as Omicron spreads in the community there will be some impact on the supply-chain, but officials are working hard to minimise it, Finance Minister Grant Robertson says.

Robertson provided an update on how officials are working to minimise the impact of Omicron, and detailed what support will be available to people affected by the outbreak at a media conference today.

Evidence from overseas shows Omicron has had an impact on the supply-chain, as thousands of workers isolate.

The government was working closely with the supermarket and supply-chain and logistics sectors to ensure there are no supply issues, and supermarket shelves remain stocked, he said.

Prime Minister Jacinda Ardern announced today the whole country will move to the red traffic light setting at 11.59pm tonight after Omicron community cases were confirmed.

She also said the government was planning on a three-staged approach to responding to Omicron. More details will be provided on Wednesday.

Based on the plans for the staged approach, if there were 25,000 cases a day there would likely be 350,000 people self-isolating, Robertson said.

"Obviously that's a significant number of people. Business continuity planning is something I know most businesses around New Zealand have been doing and they are working to see how they can manage their way through that."

There is a lot of work being done to ensure there will not be significant disruption, "but inevitably there will be some," he said.

There is a "high degree of uncertainty" for businesses, he added.

He reiterated there is no need for anyone to panic buy as supermarkets will remain open.

"Planning and preparing is a good thing, but needing to buy three trolley-loads of toilet paper is not."

Support available for cases, contacts, businesses

Robertson said support will be available to help people who are unable to be at work because they are infected or a close contact during the Omicron outbreak.

The Leave Support Scheme is available to employers and the self-employed to help pay affected workers.

It is paid at the same rates as the wage subsidy.

Shelves at Countdown, St Lukes, Auckland, were stripped of toilet paper following the announcement the country will move to red.

Shelves at Countdown, St Lukes, Auckland, were stripped of toilet paper following the announcement the country will move to red. Photo: SUPPLIED

There will also be a scheme in place for people unable to work from home when waiting on Covid-19 test results.

Other schemes, including the small business cashflow loan scheme and events transition support scheme, remain available.

Full details about these payments are on the Ministry of Social Development's website.

Robertson said there are resources within the Covid Response and Recovery Fund to manage the immediate response to Omicron.

"To be perfectly honest, we can't afford not to do it. One of the important things we know here is if people do get sick, they do need to stay home and isolate - that's how we limit the spread. And therefore, it can be a much worse situation if they didn't."

Further targeted support measures may be made available in the coming weeks, Robertson said.

"If further resources are needed to protect New Zealanders' lives and livelihoods, we will do as we have done before, and make those resources available."

New Zealand's level of debt was lower than it was forecasted, he said.

"New Zealand has one of the strongest government financial positions in the world and our government accounts continue to outperform forecasts and this gives us the fiscal headroom to meet the costs of Omicron."