Unfriendly nation, reportedly (6)
I believe the answer is:
chilly
'unfriendly' is the definition.
(I've seen this before)
'nation reportedly' is the wordplay.
'nation' becomes 'chile' (Chile is an example).
'reportedly' indicates a 'sounds like' (homophone) clue.
'chile' sounds like 'CHILLY'.
(Other definitions for chilly that I've seen before include "Descriptive of cold weather" , "Cool" , "Unpleasantly cold or unfriendly in manner" , "Unfriendly; coldish" , "Without warmth" .)