King is in France regarding large bird of prey (7)
I believe the answer is:
kestrel
'bird of prey' is the definition.
(kestrel is a kind of bird of prey)
'king is in france regarding large' is the wordplay.
'king' becomes 'K' (abbreviation for king in chess).
'is in france' becomes 'est' ('is' in French).
'regarding' becomes 're' (re can mean regarding, concerning).
'large' becomes 'L' (eg in clothes sizes).
'k'+'est'+'re'+'l'='KESTREL'
(Other definitions for kestrel that I've seen before include "It takes mice" , "Small species of falcon" , "Les, trek around the bird" , "Small type of falcon" , "Falcon that hovers" .)