Nearly 200kg of cocaine has been found in a shipment of bananas in what is New Zealand's largest cocaine bust, resulting in the arrest of an Australian man.

The bust comes after a joint Australian Federal Police (AFP) and Australian Criminal Intelligence Commission investigation into an Australian-based crime group identified a potential shipment of illicit drugs leaving Balboa, Panama, on August 4.

The shipment of bananas arrived on a vessel and arrived in Auckland on August 20.

NZ CUSTOMS/SUPPLIED About 190kg of cocaine was found in a banana shipment, making it New Zealand's largest ever drug bust.

It was inspected by both police and New Zealand customs officers.

Five duffel bags were found on top of banana boxes and contained 190 blocks of cocaine.

Each block weighed about a kilogram and had been wrapped in packaging tape.

A 41-year-old Australian man was arrested in Sydney in relation to the cocaine bust.

National organised crime group manager Detective Inspector Paul Newman said this was an extremely significant seizure for both New Zealand and Australia.

Both countries were recognised as "lucrative markets" for the illicit drug trade, he said.

"This operation has once again shown our dedication to disrupting organised crime and reducing the devastating harm that drugs cause in our community," Newman said.

"The cooperation of both law enforcement and intelligence groups during this investigation has been central to its success in targeting transnational crime."

Customs investigations manager Bruce Berry said the seizure and arrests highlight the strong partnership between Australian and New Zealand law enforcement agencies.

It showed the countries' shared focus on disrupting drug smuggling and protecting each other's borders, he said.

"This joint trans-Tasman approach is an important part of customs' strategy to keep harm offshore, and shows how New Zealand is playing its part internationally through the use of our intelligence and targeting to successfully identify risk," Berry said.

Police Minister Stuart Nash said the cocaine seizure demonstrated strength in the partnership between New Zealand and Australian law enforcement agencies in preventing drug harm.

"Targeting transnational organised crime is a priority for the Government," Nash said.

"Drugs like cocaine cause harm and fuel organised crime networks.

"This operation highlights the key role New Zealand plays internationally in disrupting transnational criminal networks," he said.

"It also showcases the fantastic work customs and police staff are doing every day to protect and keep our communities safe."

Customs Minister Kris Faafoi said he was pleased to see the focus on consignments transhipping through New Zealand had been effective.

"Additional funding this Government provided in 2018 is aimed at disrupting drugs earlier in the supply chain to prevent harm to the community - this seizure has stopped what would have been a very significant amount of harm.

"This is a good example of what we can achieve when police, border and overseas agencies work together."

Anyone who wants to report illegal drug activity can contact their nearest police station or Crimestoppers anonymously on 0800 555 111.

The discovery of the drugs in a banana shipment comes as supermarkets across the country have been experiencing a banana shortage.

A ship carrying loose bananas imported from Mexico, Ecuador and the Philippines had to change its route, a Countdown spokesperson said.

"It is a national issue but supply varies from store to store," it said.

Foodstuffs spokeswoman Antoinette Laird said the shortage was due to unforseen shipping issues but supply was expected to return to normal by the end of November.