Was against nothing papa put forward (7)
I believe the answer is:
opposed
'was against' is the definition.
(I've seen this in another clue)
'nothing papa put forward' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'papa' becomes 'P' (NATO / phonetic alphabet).
'put forward' becomes 'posed' (I've seen this in another clue).
'o'+'p'+'posed'='OPPOSED'
(Other definitions for opposed that I've seen before include "Competed with" , "Hostile to" , "Stood against" , "Objected to" , "Resisted" .)