New Zealand's declared war on the brown marmorated stink bug.

New treatment requirements are now in place that mean all imported vehicles and machinery from the United States must be heat treated or fumigated with methyl bromide before being shipped here.

The rules apply to all new and used cars, trucks, machinery, boats and parts.

In the past new vehicles were assessed on arrival by quarantine officers... and only high risk ones were treated on arrival.

MPI's biosecurity manager Paul Hallett says the main driver for the strong new rules has been the recent frequent discoveries of stink bug infestations in consignments from the United States.

The brown marmorated stink bug is an agricultural pest found in Asia, mostly China, Japan, and Korea.

But it has aggressively invaded the United States and could successfully establish in New Zealand... it's a voracious feeder and almost any crop can be at risk.