Postpone pressure after American fills post (7)
I believe the answer is:
suspend
'postpone' is the definition.
(I know that suspend is a type of prorogue)
'pressure after american fills post' is the wordplay.
'pressure' becomes 'p' (abbreviation).
'after' is a charade indicator (letters next to each other).
'american' becomes 'us' (abbreviation for United States).
'fills' indicates putting letters inside.
'post' becomes 'send' (synonyms).
'p' after 'us' is 'usp'.
'usp' put into 'send' is 'SUSPEND'.
(Other definitions for suspend that I've seen before include "Fail to hit" , "Remove temporarily from office - hang" , "Keep in abeyance" , "Ban" , "Dangle or postpone" .)