Covid-19 cases have been climbing, with experts warning we're in a new wave of the pandemic.

Some experts say New Zealand should be considered.

Auckland University Covid modeller David Welch says cases are likely to keep rising, putting extra pressure on the health system.

He says he certainly wouldn't rule out going back into red within the next few weeks -- but he concedes it may not be politically feasible.

Prime Minister Jacinda Ardern says Red Traffic Lights restrictions aren't being considered.

She says there's a real question mark over whether gathering limits at red would make a marked difference.

Auckland University epidemiologist Rod Jackson says he's been noticing people have been getting slack with the measures.

He says we need to do orange properly before talking about other restrictions, and believes if we do that, we won't need to move levels.

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