Reveal love in declaration of intent (9)
I believe the answer is:
manifesto
'declaration of intent' is the definition.
'reveal love' is the wordplay.
'reveal' becomes 'manifest' (I've seen this before).
'love' becomes 'o' (In tennis, 'love' means 'zero').
'manifest'+'o'='MANIFESTO'
'in' is the link.
(Other definitions for manifesto that I've seen before include "Publication containing political programme" , "Soften aim (anag) - platform" , "Statement of policies" , "Pre-election policy declaration" , "Pre-election promises" .)