Embargo, ban (7)
I believe the answer is:
boycott
This clue is a double definition.
'embargo' is the first definition.
(I've seen this before)
'ban' is the second definition.
(thesaurus)
(Other definitions for boycott that I've seen before include "Punitive ban" , "industrial action" , "Refuse to trade with" , "Blackball" , "Ostracise" .)