I'd return to break agreement in dispute (10)
I believe the answer is:
contradict
'dispute' is the definition.
(thesaurus)
'i'd return to break agreement' is the wordplay.
'return' says the letters should be written in reverse.
'to break' indicates putting letters inside.
'agreement' becomes 'contract' (contract is a kind of agreement**).
'id' in reverse letter order is 'di'.
'di' placed inside 'contract' is 'CONTRADICT'.
'in' is the link.
(Other definitions for contradict that I've seen before include "Have a different view" , "Argue against" , "dispute" , "Deny" , "Be in conflict with" .)