Former Madhya Pradesh CM, Singh claimed in Rajya Sabha on Aug 11 that Rao, who was the Union home minister in 1984, played a role in the release of Union Carbide chief Warren Anderson.
The eldest son of the former PM, P V Ranga Rao said, "Father could not have taken a decision of this magnitude on his own, many other ministries and persons had to be involved in it."
"Any important decision having international ramifications could not be taken by an individual minister. The allegations against him are not only unfair but also against Indian culture," said Ranga Rao to Indian Express.
He also said to the daily, "Is it fair to indict my father who is not here in this world to defend himself?"