Under debate (2,5)
'under debate' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for at issue that I've seen before include "Being discussed or disputed" , "in dispute" , "under debate" , "In question, under discussion" , "Questionable" .)
'under debate' is the definition.
(I've seen this in another clue)
This is all the clue.