America finished importing European sap (3,2)
I believe the answer is:
use up
'sap' is the definition.
(synonyms)
'america finished importing european' is the wordplay.
'america' becomes 'US' (United States).
'finished' becomes 'up' (eg 'time's up' means the time is finished).
'importing' indicates putting letters inside.
'european' becomes 'E' (abbreviation e.g. EU).
'us'+'up'='usup'
'usup' enclosing 'e' is 'USE UP'.
(Other definitions for use up that I've seen before include "Consume (stocks)" , "Expend" , "Completely consume" , "Exhaust (resources)" , "Finish, exhaust" .)