Arab statesman soon to make a comeback (5)
I believe the answer is:
omani
'arab statesman' is the definition.
(someone from Oman)
'soon to make a comeback' is the wordplay.
'soon' becomes 'in a mo' (in a mo).
'to make a comeback' says the letters should be written in reverse (I've seen 'making a comeback' mean this).
'inamo' in reverse letter order is 'OMANI'.
(Other definitions for omani that I've seen before include "Eg, a native of Muscat" , "Citizen of a country, capital Muscat" , "Asian" , "One from Muscat" , "Gulf Arab" .)