Intricate red lace, say (7)
I believe the answer is:
declare
'say' is the definition.
(I know that declare is a more specific form of the action affirm)
'intricate red lace' is the wordplay.
'intricate' is an anagram indicator.
'red'+'lace'='redlace'
'redlace' with letters rearranged gives 'DECLARE'.
(Other definitions for declare that I've seen before include "Proclaim" , "State clearly, announce officially" , "Announce; end innings" , "Announce formally" , "Make a statement, to customs perhaps" .)