First-class state leader (7)
I believe the answer is:
premier
'leader' is the definition.
(I know that premier is a type of head of state)
'first-class state' is the wordplay.
I cannot really understand how this works, but
'first' could be 'i' (I in Roman numerals eg Elizabeth I) and 'i' is found within the answer.
'class' could be 're' (Religious Education, school subject) and 're' is found in the answer.
'state' could be 'me' and 'me' is found within the remaining letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for premier that I've seen before include "First in importance" , "Prime minister" , "Earliest" , "Which is having precedence" , "Aberdeen or Salisbury?" .)