It is a Quoll.

Quolls (/ˈkwɒl/; genus Dasyurus) are carnivorous marsupials native to mainland Australia, New Guinea and Tasmania. See Wikipedia.

Then of course why the quoll?

1. Well it is local to the NT.
2. It is small.
3. And it is fast.
4. It is cute.
5. And it is probably the most dangerous animal per gram in Australia.

But don't call it a rat :-), at least in front of Phil.