Armistice is cute, arranged around Republican (5)
I believe the answer is:
truce
'armistice' is the definition.
(I know that armistice can be written as truce)
'cute arranged around republican' is the wordplay.
'arranged' indicates an anagram (letters rearranged).
'around' is an insertion indicator.
'republican' becomes 'R' (political abbreviation).
'cute' with letters rearranged gives 'tuce'.
'tuce' enclosing 'r' is 'TRUCE'.
'is' is the link.
(Other definitions for truce that I've seen before include "Suspension of hostilities" , "Cessation of hostilities to allow peace talks" , "Agreed break in hostilities" , "Agreement to stop fighting temporarily" , "Temporary halt in hostilities" .)