A "loophole" law allowing patients to import medicinal marijuana into New Zealand will not be changed, according to Associate Health Minster Peter Dunne.

The loophole means anyone entering the country can lawfully carry with them a one-month supply of medicinal cannabis or cannabis-related product, as long as it was legally prescribed by a medical practitioner overseas.

Dunne confirmed that it was "potentially possible" to bring a medicinal cannabis product prescribed overseas for their own use for a maximum of one month, without repeat.

"That has been in the law for over 40 years, and applies to all medicinal products, not just cannabis related products," he said.

Dunne said any importation of a cannabis-related product would be subject to border control requirements but that it will not be possible to bring in raw cannabis as it is prohibited by law.

"I am not proposing any immediate action in respect of this provision, but will monitor the situation if and when cannabis-related products become an issue,"...