I will, I say. I see it is not permitted (7)
I believe the answer is:
illicit
'is not permitted' is the definition.
(I've seen this in another clue)
'i will i say i see it' is the wordplay.
'i will' becomes 'I'll' (abbreviation).
'i say i' becomes 'ic' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ill'+'ic'+'it'='ILLICIT'
Can you help me to learn more?
(Other definitions for illicit that I've seen before include "completely banned" , "Illegal" , "criminal" , "not conforming to regulations" , "Without approval" .)