Heat of conflict close to Arnhem (4)
I believe the answer is:
warm
'heat' is the definition.
(I've seen this before)
'conflict close to arnhem' is the wordplay.
'conflict' becomes 'war' (war is a kind of conflict).
'close to' says to take the final letters (the close/ending of).
The last letter of 'arnhem' is 'm'.
'war'+'m'='WARM'
'of' acts as a link.
(Other definitions for warm that I've seen before include "Heated; enthusiastic" , "Friendly" , "Passionate; ardent" , "Pleasantly hot" , "easily aroused" .)