Joint resolution of Kremlin was regularly ignored (5)
I believe the answer is:
ankle
'joint' is the definition.
(ankle joint is a kind of joint)
'resolution of kremlin was regularly ignored' is the wordplay.
'resolution of' indicates anagramming the letters (I've seen 'resolution' mean this).
'regularly ignored' indicates alternate letters (letters removed at regular intervals).
'kremlin'+'was'='kremlinwas'
The alternating letters of 'kremlinwas' are 'kelna'.
'kelna' is an anagram of 'ANKLE'.
(Other definitions for ankle that I've seen before include "Human joint" , "Foot-leg connector" , "Narrow part of leg" , "Lower leg joint" , "Low joint" .)