Spanish leader loses nothing but money (5)
I believe the answer is:
franc
'money' is the definition.
(former currency of France)
'spanish leader loses nothing' is the wordplay.
'spanish leader' becomes 'franco' (I've seen this in another clue).
'loses' suggests deleting specific letters.
'nothing' becomes 'O' (O resembles 0).
'franco' with 'o' taken away is 'FRANC'.
'but' acts as a link.
(Other definitions for franc that I've seen before include "Former French monetary unit" , "Old French coin" , "Historic currency" , "Unit of money" , "Ex-Gallic coin" .)