Associate Health Minister Peter Dunne is welcoming changes to Australia's Narcotic Drugs Act.

The Australian Parliament will allow the growth of medical marijuana, but Australians still won't be able to use it, unless further laws are changed.

Peter Dunne said "all Australia has done is catch up with where New Zealand has been for some time, it's been permissable in New Zealand for some time to cultivate crops for the purposes of conducting clinical trials."

He suspects a particular investor interested in trials prompted the law change.

"It may lead to outcomes that could be favourable here, but I'm not expecting anything dramatic or sudden."

"It's still some years away."

The country's health department is also considering rescheduling medicinal cannabis, which is still classified as an illicit drug.

Dunne said if a medicinal cannabis product was registered in Australia it's highly likely we would follow suit.