Prime Minister Jacinda Ardern said New Zealanders should expect big restrictions on their interactions with other people when the country moves to alert level 3.

She told Chris Lynch on Newstalk ZB that it still wasn't known exactly when New Zealand would move down from its current level 4 to the lower level.

Other countries which were now extending their lockdown because they introduced the restrictions later, she said.

The Government would provide details on how it would impact schools, business, workplaces and other sectors this afternoon, she said.

Asked about small to medium businesses struggling during lockdown, she said Government knew they were vulnerable.

She cited the support the Government had provided, in particular, with the wage subsidy but also changes around rent arrears and tax changes.

"They really have been a big focus for us."

Ardern said all New Zealanders had the "sad benefit" of experiencing lockdown later than others.

New Zealand's approach worked for both the health of the country and the economy, she said.

She said she had discussed with other global leaders what it could look like if countries had a second wave of coronavirus.

She wanted to focus on elimination to minimise the effect of coronavirus on New Zealanders' daily lives.

Asked about price-gouging, Ardern said the Government had been quick to respond where it saw over-charging.

She said in some cases seasonal changes were to blame for high prices - like cauliflower - rather than price-gouging.

Ardern said she got updates on global research on coronavirus vaccines and treatment drugs.

New Zealand was part of the global research effort in these areas, she said.

The confidential reports she was getting were the same as the public reports - that a vaccine was likely to take at least 12 months.

The four-week lockdown officially ends next Wednesday night, at 11.59pm, but the Government won't announce whether we move down a level until next week.

However, New Zealanders will today get to hear about what life looks like after lockdown - expect to see pubs and food courts still closed but potentially takeaways allowed and more police on the roads.

The Government will release guidance around alert levels 3 and 2 and what measures businesses would need to have in place at each step.

But it will likely still be quite restrictive with Finance Minister Grant Robertson calling it a move from "essential" to "safe" businesses.