Reluctantly deliver expression of horror to disrupt power grab (5,2)

I believe the answer is:
cough up
'power grab' is the definition.
The answer and definition can be both to do with ownership as well as being verbs in their base form.
Perhaps they are linked in a way I don't understand?
'reluctantly deliver expression of horror to disrupt' is the wordplay.
I cannot quite see how this works, but
'expression' could be 'ugh' (I have seen 'Expression of disgust' mean 'ugh' so perhaps 'expression' could also mean 'ugh') and 'ugh' is found in the answer.
'of' could be 'o' and 'o' is found in the answer.
The remaining letters 'cup' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for cough up that I've seen before include "Clear throat and pay what you owe" , "Clear throat to part with money" , "(Reluctantly) contribute" , "Pay out under duress" , "Pay money with some reluctance - clear throat" .)