Ex-leader's requests are largely ignored (4)
I believe the answer is:
tsar
'ex-leader's' is the definition.
(historical Russian leader)
'requests are largely ignored' is the wordplay.
'largely ignored' indicates the answer is hidden within the clue (most of the letters must be ignored).
'TSAR' is hidden within 'requests are'.
(Other definitions for tsar that I've seen before include "Nicholas II was the last" , "Autocrat" , "Male monarch" , "Star for a Russian emperor" , "Russian ruler (S, not Z)" .)