Bihar Chief Minister Nitish Kumar on Friday declared that he will not realign with the BJP as long as he is alive, accusing the former ally of using investigating agencies for targeting political opponents like RJD president Lalu Prasad.

Addressing a function in this north Bihar district, where he inaugurated a government engineering college, Nitish charged the current BJP leadership with arrogance and wistfully recalled the era of Atal Bihari Vajpayee, Lal Krishna Advani and Murli Manohar Joshi.

"They lodged a case against Lalu ji, which caused me to sever my ties with him. Nothing came of it. And now when we are together again, they are lodging fresh cases. You can figure out the style of functioning of these people," Nitish told the gathering, without mentioning the BJP by name.

Prasad was named in an IRCTC land for hotels scam a few years ago in which his son Tejashwi Yadav, then serving his first tenure as Deputy CM, was also named an accused. This had unsettled Kumar, who sets much store on his reputation for personal probity, and led to his return to the NDA.

The RJD president and his family members were recently charge-sheeted in another land for jobs scam, pertaining to Lalu's tenure as railway minister in the UPA-1 government.

"So different were the leaders of the same party of the past like former Prime Minister Atal Bihari Vajpayee, in whose cabinet I had the privilege to work, and LK Advani who was then the Deputy PM. I have fond memories of Murli Manohar Joshi too who honored my request to upgrade my alma mater, the Bihar Engineering College, as a National Institute of Technology," said Nitish.

"In contrast, those currently at the helm of affairs listen to nobody, and have scant respect for any person and his or her concerns. I want to assert that I will not go back to them as long as I am alive," said the JD(U) leader, who had dumped the BJP two months ago over accusations of attempts to split his party.

Referring to the multi-party 'Mahagathbandhan' he has joined, which includes RJD, Congress and three Left parties, Nitish vowed "we are all socialists by conviction. We will remain together and work for the progress of the nation".

After snapping ties with the BJP, the longest-serving chief minister of Bihar has become a strong votary of "opposition unity" and claims that it would ensure the defeat of the BJP, which at present appears formidable.