Leaders of old regime had to speak in public? (5)
I believe the answer is:
orate
'speak in public?' is the definition.
(I've seen this in another clue)
'leaders of old regime had' is the wordplay.
'leaders of' suggests taking the first letters.
'had' becomes 'ate' (e.g. I had an ice cream).
The initial letters of 'old regime' is 'or'.
'or'+'ate'='ORATE'
'to' is the link.
(Other definitions for orate that I've seen before include "make speeches" , "Speak publicly" , "Erato (anag.)" , "Speak like Cicero?" , "Declaim or rant" .)