Mr Ban told a news conference on Sunday at the summit of the world's 20 leading economies, the G20, that there needed to be a "robust" response to the horrific attacks in Paris which killed at least 129 people.
Ban akizungumza kwenye ufunguzi wa mkutano wa kimataifa wa siku tatu wa maspika wa bunge mjini Geneva amesema hivi karibuni tumeona dalili za kupiga hatua kuhusu suala la uzalishaji wa nyuklia.