Read South American country's leading journalist (7)
I believe the answer is:
perused
'read' is the definition.
(I've seen this before)
'south american country's leading journalist' is the wordplay.
'south american country's' becomes 'Peru's' (country in South America).
'leading journalist' becomes 'ed' (short for editor).
'perus'+'ed'='PERUSED'
(Other definitions for perused that I've seen before include "Studied" , "Read (something) very carefully" , "Browsed" , "Scanned" .)