Authorisation to cut benefit for diplomat (10)
I believe the answer is:
permission
'authorisation' is the definition.
(permission is a kind of authorisation)
'cut benefit for diplomat' is the wordplay.
'cut' means to remove the last letter.
'benefit' becomes 'perk' (perk is a kind of benefit).
'for diplomat' becomes 'mission' (I am not sure about this - if you are sure you should believe this answer much more).
'perk' with its final letter taken off is 'per'.
'per'+'mission'='PERMISSION'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for permission that I've seen before include "Leave" , "Allowance" , "Consent, authorisation" , "Visa, eg" , "Green light" .)