Appropriate international body first out of condition (5)
I believe the answer is:
unfit
'out of condition' is the definition.
('unfit' can be similar in meaning to 'out of condition')
'appropriate international body first' is the wordplay.
'appropriate' becomes 'fit' ('fit' can be similar in meaning to 'appropriate'**).
'international body' becomes 'un'.
'first' is a charade indicator (letters next to each other).
'fit' put after 'un' is 'UNFIT'.
(Other definitions for unfit that I've seen before include "Ill - out of shape" , "Incapable" , "Not prepared" , "In poor condition" , "Incompetent" .)