Stop and go after amber changes (7)
I believe the answer is:
embargo
'stop' is the definition.
(I know that embargo is a more specific form of the action stop)
'go after amber changes' is the wordplay.
'after' is a charade indicator (letters next to each other).
'changes' indicates an anagram.
'amber' is an anagram of 'embar'.
'go' after 'embar' is 'EMBARGO'.
'and' is the link.
(Other definitions for embargo that I've seen before include "Trade barrier or publication ban" , "Government trade ban" , "Trading restriction" , "Block" , "Trading ban" .)