New Zealand one of the hardest countries to invade - report

Being a small country down the bottom of the world might make trade and travel difficult for Kiwis - but it may have one important advantage.

New Zealand is one of the hardest countries in the world to invade, according to a report by Swedish newspaper Svenska Dagbladet.

The study assesses the military power, size of the country and the difficulty of terrain to determine the country's defensive capability.

The authors say conquering us would be extremely difficult from a logistical point of view. New Zealand is around 2000km from Australia, hindering supply chains and making planning an invasion a "nightmare".

"Getting your troops, and supplying them with necessities, seems almost an impossibility," the newspaper says.

Other countries to make the cut include Switzerland, described as "extremely difficult" due to being surrounded by the Alps, while Russia has difficult terrain and thousands of years of experience with wars.