Let me make this clear: you don’t have to listen (4,2,4)
I believe the answer is:
read my lips
'let me make this clear' is the definition.
(phrase used to emphasise what you're saying)
'you don't have to listen' is the wordplay.
I cannot quite understand how this works, but
'have' could be 'read' (reading is a kind of having) and 'read' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for read my lips that I've seen before include "I promise you" , "Electoral pledge (to deaf audience?)" , "Listen carefully!" .)