Impossible, however you look at it (3,2)
I believe the answer is:
not on
I believe this clue is a double definition.
'impossible' is the first definition.
(I've seen this before)
'however you look at it' is the second definition.
(Other definitions for not on that I've seen before include "Modern usage for unacceptable" , "taboo" , "Impractical" , "Unacceptable (colloq.)" , "Colloquially, cannot be tolerated or accepted" .)