Our narrow separation from the EU (7,2,5)

'the eu' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'our narrow separation from' is the wordplay.
I cannot really see how this works, but
'narrow' could be 'strait' (similar in meaning) and 'strait' is found in the answer.
'from' could be 'of' (I've seen this in other clues) and 'of' is found in the answer.
This explanation may well be incorrect...