I suppose the equivalence of a state in Britain is a kingdom, or perhaps a duchy? At any rate the Duchy of Devonshire I suppose. Or would it be districts???
As states could freely join the US (But not leave it), just like Scotland and England united, I'd say the countries of the UK are the same as states. Well, a bit...let's not get into political details.
I'm from the wonderful social and open-minded place called the Netherlands. South, to be exact.