Truth must come out and whatever documents are there should be in public domain, he told PTI insisting that this was necessary in view of doubts.
Shastri has earlier said there were suspicion that some "foul play" could have led to his death in Tashkent nearly 50 years ago.
He also recalled that BJP has all along been demanding that the files relating to Shastri's be de-classified.
Another son of the former PM Sunil Shastri, a BJP leader, also said that he has been requesting several Prime Ministers in the past to de-classify files pertaining to his father.
The demand comes close on the heels of West Bengal government declassifying files on Netaji Subhash Chandra Bose.