New Zealanders are stocking up on firearms in their droves ahead of the closure of gun stores due to the coronavirus pandemic.

On Monday, the Prime Minister announced all non-essential businesses - which includes gun shops - would close for at least four weeks from 11:59pm Wednesday, when New Zealand escalates its COVID-19 alert level from 3 to 4.

The announcement has clearly instilled panic in Kiwis, who are queuing in large numbers outside firearm retail outlets.

One video, sent to Newshub by Brad Pivac, shows dozens of people lining around the building outside Gun City in Wairau Park on Auckland's North Shore.

Photos taken outside Gun City in the central Auckland suburb of Penrose shows similar scenes - queues snaking round the block as people wait to stock up on firearms and ammunition.

Ralf Klis, an Aucklander who witnessed the scene, told Newshub the queues were akin to those seen outside PAK'nSAVE in the throes of supermarket panic-buying.

Police say they are aware of the queues and are "currently monitoring the situation".

"Police attended this morning between 7am and 8am, and provided reassurance advice to both members of public and staff at the store," a statement sent to Newshub read.

"Our priority as police is to keep all New Zealanders safe, and we want to remind people not to panic in this unprecedented time, maintain a safe distance from others, look after one another and stay safe."

Panic-buying has proven to be a major unintended problem caused by the coronavirus outbreak.

When Jacinda Ardern made her COVID-19 announcement on Monday, supermarkets across New Zealand were overrun with Kiwis scrambling to get their hands on groceries.

That's despite supermarkets coming under the banner of essential services, and thus remaining open even when New Zealand goes ramps up to coronavirus alert level 4.