King perhaps wants an end to hostilities declared (5)
I believe the answer is:
piece
'king perhaps' is the definition.
(king is a chess piece)
'an end to hostilities declared' is the wordplay.
'an end to hostilities' becomes 'peace'.
'declared' shows a homophone (sound like).
'peace' is a homophone of 'PIECE'.
'wants' acts as a link.
(Other definitions for piece that I've seen before include "Segment" , "bishop on board, say" , "Slice" , "Chessman; portion" , "Component; portion" .)