NZ Customs unveil their largest ever seizure of meth hidden inside the doors of shipping containers.

Nearly 180kg of P has been seized by Customs staff - a record-breaking haul.

Customs said a "tenacious investigation and good intelligence" were to thank for intercepting 176kg of pure methamphetamine, which is said to have a potential street value of $176 million.

The meth packages was discovered concealed in July in the walls and doors of 10 shipping containers sent from China.

Supplied/NZ Customs About 176kg of methamphetamine was found by Customs after a Hong Kong man allegedly tried to smuggle it into New Zealand.

Customs spokesman Jamie Bamford said the smugglers went to great lengths to try and hide the class A drug.

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The packages were in welded into the metal framing of the doors of the containers, which were otherwise transporting scaffolding and tissue paper.

Supplied/NZ Customs The drugs were hidden inside these packages.

"It was a clever concealment."

He said the meth would now be disposed of in a secure facility.

Bamford said the seizure, which was the largest ever by customs, was the result of a 16-month investigation.

Supplied/NZ Customs The methamphetamine found by customs staff.

Further investigations allegedly linked the shipment to a 20-year-old Hong Kong man, who appeared in court on Friday morning.

He was arrested following two search warrants in Auckland in early October, where further evidence of his involvement was found, Bamford said.

The seizure is expected to make a significant dent in the methamphetamine supply chain.

"This seizure will have prevented New Zealand's criminal gangs from profiting from the misery caused by pushing meth through our cities and rural communities," Bamford said.

Further arrests have not been ruled out, as investigations continued.

It comes after police, in June, made a discovery of almost 500kg of methamphetamine in sand dunes in Northland.

Based on the NZ Drug Harm Index, this latest seizure has prevented a potential social harm of up to $218 million.

"As with all our investigations, we will also liaise with our overseas customs counterparts for follow-up investigations in China and Hong Kong," Bamford said.

The man is set to reappear in the Auckland District Court on November 17.