Salman Rushdie and his supporters are the only people to blame for Friday's attack on the novelist, Iran's Foreign Ministry said on Monday.
Rushdie is recovering after being stabbed repeatedly at a public appearance in New York state.
Freedom of speech does not justify Rushdie's insults against religion in his writing, ministry spokesperson Nasser Kanaani told a news briefing.
The Indian-born writer has lived with a bounty on his head since the publication of his 1988 novel "The Satanic Verses," which is viewed by some Muslims as containing blasphemous passages.
In 1989 Iran's then Supreme Leader Ayatollah Ruhollah Khomeini issued a fatwa, or edict, calling on Muslims to kill the novelist and anyone involved in the book's publication.
The Iranian government said in 1998 it would no longer back the fatwa, and Rushdie has lived relatively openly in recent years.
"Salman Rushdie exposed himself to popular outrage by insulting Islamic sanctities and crossing the red lines of 1.5 billion Muslims," Kanaani said.
"During the attack on Salman Rushdie, we do not consider anyone other than himself and his supporters worthy of reproach, reproach and condemnation...No one has the right to accuse Iran in this regard."
He said Iran had no other information about Rushdie's assailant except what had appeared in media.