"There is no record whatsoever in our parliamentary history that Nehru consulted his cabinet before going to the United Nations with the issue," Swamy said at a book release function here.
Nehru's agreement to a plebiscite on Jammu and Kashmir's accession to India was illogical as there were states with Hindu majority that went to Pakistan simply because their rulers signed agreements with the Pakistan government, he said.
"It was his mistake and the subsequent governments are not bound to follow what he did personally," he said.
The Congress is holding an international conference to mark Nehru's 125th birth anniversary. However, the party neither invited the BJP nor Prime Minister Narendra Modi.
Swamy said agreeing to a plebiscite in Kashmir was a mistake.
Swamy said agreeing to a plebiscite in Kashmir was a mistake
"It was being decided by the rulers of the respective states whether to get hooked to India or to Pakistan," he said, accusing Nehru of being short-sighted on the issue.
Swamy said the instrument of accession came into force after Pakistan was created out of India, and if creation of Pakistan was legal, then the legality of the instrument of accession cannot also be questioned.
Nehru also got Article 370 inserted, which gives special status to Jammu and Kashmir, in the original copy of the constitution.
This was strongly opposed by B.R. Ambedkar, chairman of the drafting committee of the constitution, Swamy said.
The book titled "Plight of Jammu and Kashmir - the unknown files", by former Jammu and Kashmir High Court judge G.D. Sharma, gives an insight into the state's creation.