Keshubhai, who has twice been the chief minister has been vocal in his criticism of Chief Minister Narendra Modi, calling him a "demon" responsible for the misery of common people of the state.
The veteran BJP leader had announced he will soon float a new party and has received support of other Modi detractors like Kanshiram Rana, Fakir Vaghela, Suresh Mehta Nalin Bhatt and Gordhan Zadafia.
He has been upset with the party for sidelining him. Keshubhai had earlier said the situation in the state had become "worse" than the Emergency era.
The former chief minister of Gujarat, who was replaced by Narendra Modi in 2001, has been targeting the BJP stalwart in the run-up to the state elections scheduled in December.
"Narendra Modi is a demon who is responsible for the misery of common people of Gujarat. As per our ancient tales, the life of demons used to be in some bird. To win the fight against such demons, the hero has to kill the bird. In the same way, Modi's life is in your votes. Do not give him vote and he will be finished," Keshubhai had said.
Keshubhai had also compared Modi to Adolf Hitler. Sharpening his attack on Modi, Keshubhai had also compared him with thick skinned animal rhinoceros for being "insensitive" towards people's problems and a "decayed fruit" that should be thrown out.
Insensitivity has become a hallmark of the present government. Modi is like a "rhinoceros" and "decayed fruit" that should be thrown out, he said.
"This government is doing injustice to people. Women and children are not safe and the State Government was not concerned because it is insensitive towards people's problems," the former chief minister had alleged.