UPDATED 5.30pm A staggering increase in the amount of methamphetamine being seized at New Zealand's borders.

Figures released to Newstalk ZB under the Official Information Act show the quantity of the drug being intercepted by Customs has increased more than 35 times in the past few years.

LISTEN ABOVE: Newstalk ZB reporter Michael Allan and Criminologist Greg Newbold spoke with Andrew Dickens about the findings

In 2009, a little under 10 kilograms of the class A drugs were seized. 

But up until the end of August this year, more than 357 kilograms was stopped at the border by Customs officials.

That's a street value of more than $357 million.

353 out of the 357 kilograms was intercepted in Auckland.

Drug Foundation CEO Ross Bell said the surge can be put down to a flexible drug market.

"Increasingly we're seeing a move away from methamphetamine being manufactured in New Zealand...a few years ago we saw ingredients for methamphetamine coming across the border," he said.

Addiction Treatment National Committee Chair Dr Vanessa Caldwell said the surge in seizures isn't being felt on the streets.

"Certainly the communities are telling us that it's easy to get on the streets and it's very prevalent.

"There's still some getting through."

Criminologist Greg Newbold thinks the skyrocketing levels of the drug being found at our borders could mean we're becoming something of a P staging post.

He said the market price is stable at $600 to $800 a gram - which suggests supply is steady.

CEO of Australia's Alcohol and Drug Foundation John Rogerson told Rachel Smalley it's certainly possible. 

"But I think it's probably unlikely really, given the price of meth in New Zealand. The market's driven by profit and there's huge profit to be made. It sounds like there's a lot of money being made in New Zealand at the moment."

John Rogerson says meth is selling for up to $300 more a gram in New Zealand than it is in Australia.

Interceptions of ingredients for methamphetamine drop

While methamphetamine interceptions have skyrocketed, the amount of P ingredients being found has dropped.

In 2009, more than a tonne of pseudoephedrine was stopped by Customs. So far in 2016, just over three and half kilos has been found.

But seizures of ephedrine, another ingredient for the manufacture of P, has risen. In 2009, almost 96 kilos of the product was stopped.

This year, that leaps to more than 760 kilograms. And in 2015, more than 900 kilograms was seized.

Staff numbers drop

In the same period, from 2009 to 2016, the number of operational Customs staff has dropped from 572 to 501.

The majority of those 71 losses were in Auckland, where 53 people lost their jobs.

Ross Bell said the reduction is probably down to better technology.

"New screening devices at the border, better intelligence gathering, they know now what to look for in the mail."