Mosque encouraged to welcome head of state (5)
I believe the answer is:
queen
'head of state' is the definition.
'mosque encouraged to welcome' is the wordplay.
'to welcome' says the answer is hidden in the clue (I've seen 'welcoming' mean this).
'QUEEN' can be found hidden inside 'mosque encouraged'.
(Other definitions for queen that I've seen before include "who collaborated musically with 14 [BOWIE]" , "Ruling lady" , "Rock group; royal personage" , "Regina" , "She commands" .)