"I am glad. She (Sonia Gandhi) should write her book. I am looking forward to it," said the former External Affairs Minister, who has been sharply critical of the Congress leadership in his book 'One Life is Not Enough'.
He was speaking to reporters outside Parliament where he had come to witness the ongoing session.
The Congress President too had reacted sharply to the contents of the book and had said that she would also pen a book.
On other Congressmen too planning to come out with their books, he said, "The more they write, the better it is".
Responding to Congress' criticism over the book, Singh said those "attacking me are petty people".
He added more than 50,000 copies have been sold in a week and the response has been tremendous.
"I had expected that around 10,000-12,000 copies would be sold, but the response has been really good," Singh said.