Panic buying has seen supplies of Covid medication fly off the shelves from some Auckland supermarkets and pharmacies ahead of the looming Omicron outbreak.

At 11.59pm last night the country moved back to the red traffic light setting in an effort to slow down the virus and it appears that people have listened to the Ministry of Health's advice to have pain relief on hand.

Perplexing pictures show just a handful of pain relief stock left at Countdown in New Lynn and at a Chemist Warehouse.

Countdown New Lynn have put this sign up with the pain relief medications. Photo / Supplied

In the event of testing positive for Omicron and having to stay home, the Ministry of Health advised having pain relief such as ibuprofen and Panadol to hand, as well as a kit with hand sanitiser, masks, tissues and cleaning equipment such as gloves, rubbish bags and cleaning products.

In less mundane fashion, a New World supermarket has limited the number of Trumpet ice creams customers can purchase.

There is also a restriction on Trumpet ice creams at this New World supermarket. Photo / Supplied

At yesterday's unscheduled press conference, Prime Minister Jacinda Ardern had not even finished making the announcement before long queues at some supermarkets had formed.

Shoppers trolleys at New World in New Lynn were seen full to the brim and Countdown Kelston customers experienced long waits to get to the checkout.

Finance Minister Grant Robertson said there was no need to rush to the shops.

"There is absolutely no need to be out there panic buying...we are asking people to think about what stocks they need if you do get sick, but there is plenty of time for that," Robertson said.

"It's been tough for the last few years for people organising events, but we know they have been planning for this."