Nitish Kumar dumped the BJP last year and ended the 17 years old alliance of his Janata Dal-United with the BJP over Modi's rise.
Modi is eyeing Bihar after Uttar Pradesh to get as much of 40 Lok Sabha seats.
The BJP has joined hands with the Lok Janshakti Party of Ram Vilas Paswan, a Dalit leader, and the Rashtriya Lok Samta Party of Upendra Kushwaha, a backward caste leader.
