Mishra, key aide of former Prime Minister Atal Bihari Vajpayee, said Modi becoming prime minister depends entirely on BJP getting a majority in Parliament on its own.
"First of all, we must be clear that BJP is not going to get majority on its own. Impossible. And therefore, he (Modi) cannot be put forward as a successor. They will have to find somebody else," Mishra told CNN-IBN.
Mishra said Modi continued as Chief Minister of Gujarat after the post-Godhra riots because the BJP wanted him to and Vajpayee did not overrule the party opinion.
However, he pointed out that Vajpayee, though endorsing the majority opinion, did advice Modi to follow 'raj dharma'.
"In Goa, there was a vociferous demand for Narendra Modi to continue as Chief Minister. He (Vajpayee) was not going to interfere. So he said this is alright but he (Modi) should follow raj dharma. It was a kind of advice given to him (Modi). But there was no question of Atalji overruling the party," Mishra said.