Vikram accepts in front of everyone that
1. He did feel like marrying Sathya before she married Arjun, but it is in past.
2. He did tell Saranya that their marriage is a deal and he will never give a place of wife to her.
However when it comes to vaada, he stays mum.
Sathya speaks here and tells Saranya that even if there is a promise between me and Vikram, it's between us and you have no rights to ask us about it.
bold yes and pakhi ( i always get confuse between character name of tamil version) has whole right to ask what is going on between husband and wife