United Nations to conflict with Germany? That's inconvenient! (8)
I believe the answer is:
untoward
'inconvenient' is the definition.
(I've seen this before)
'united nations to conflict with germany?' is the wordplay.
'united nations' becomes 'un' (synonyms).
'conflict' becomes 'war' (war is a kind of conflict).
'with' is a charade indicator (letters next to each other).
'germany?' becomes 'd' (international vehicle registration code).
'un'+'to'+'war'+'d'='UNTOWARD'
'that's' is the link.
(Other definitions for untoward that I've seen before include "vexing" , "Unexpected, inappropriate" , "Adverse - out of the ordinary" , "Inopportune" , "Unfortunate or adverse" .)