Nitish Kumar had quit the alliance, comprising the JD(U), the RJD and the Congress, in July 2017.
Chief Minister Nitish Kumar on Tuesday attributed his sudden exit from the opposition alliance to Congress president Rahul Gandhi's "inability" to take a stand on corruption charges against his former deputy and Rashtriya Janata Dal (RJD) leader Tejashwi Yadav.
Nitish Kumar, who also heads the Janata Dal (United), claimed that his party was instrumental in the Congress getting 40 seats to contest in the 2015 assembly polls.
The chief minister said he had felt let down by Mr Gandhi, then the party's vice-president, when he "did not come up with even a statement that could have made me have second thoughts (about leaving the alliance)".
Nitish Kumar had quit the alliance, comprising the JD(U), the RJD and the Congress, in July 2017 after the CBI lodged an FIR against Tejashwi Yadav on corruption charges and the strife that followed between him and the RJD.
"It has been always my line that there will be no compromise on crime, corruption and communalism. Their (RJD's) style of functioning was such that it was becoming increasingly difficult for me to work. There was interference at all levels. Their people would telephone police stations with their own decrees," Nitish Kumar claimed.
He was speaking at an event here organised by a private news channel.
"Rahul Gandhi had famously tore that ordinance. It was the JD(U) which insisted that it (Congress) be given 40 seats and they ended up winning 28. The RJD, despite its old association with it, was never ready to give it that much weightage," Nitish Kumar said.
In 2003, Mr Gandhi had torn an ordinance brought by the Manmohan Singh government with a provision to protect convicted politicians against disqualification.
Stating that he resigned as he had no other choice, Nitish Kumar said his resignation was immediately followed by an offer of support from the BJP. "So I took the decision (to join hands with the BJP) in the interests of Bihar," he said.
"We have our differences on issues like Ayodhya, Article 370 and Uniform Civil Code since the 1990s. My association with the BJP predates the National Democratic Alliance's (NDA) formation in 1999. But we have always worked amicably. Even now, we are getting full cooperation from the Narendra Modi government," he said.
Nitish Kumar had snapped ties with the BJP in 2013 following differences over projection of Narendra Modi, the then Gujarat chief minister, as the prime ministerial candidate.
On a query about the Rashtriya Swayamsevak Sangh, he said, "I may not agree with their thoughts but I cannot help admiring their consistency and commitment towards organisation building, something those adhering to our socialist ideology never excelled at."
Recalling the stupendous performances by the JD(U)-BJP combine in 2009 Lok Sabha polls and the assembly elections a year later, Nitish Kumar said, "Now we have an important leader like Ram Vilas Paswan with us. So there is no reason why we should not do even better in the upcoming Lok Sabha polls."
On the opposition ''mahagathbandhan'' (grand alliance), which comprises the RJD, the Congress, the Rashtriya Lok Samata Party (RLSP), the Hindustani Awam Morcha (HAM) and some smaller parties, he said, "Even the term mahagathbandhan that they keep flaunting was given by me. After the exit of JD(U), it is just a gathbandhan (alliance)".
"The opposition in Bihar is in panic. So it keeps adding more allies to its flock," Nitish Kumar remarked dismissively when asked about many parties, including former NDA allies like RLSP and HAM, gravitating towards the alliance.
On the RJD's opposition to the quota for upper castes, Nitish Kumar, whose party voted in favour of the bill in Parliament, said social changes have led to a sizeable growth in the number of poor among the unreserved category.
"When they are being helped without infringing on the rights of SCs, STs and OBCs, there should be no complaints," he said.
He also asserted that the NDA will face no major problems in the Lok Sabha polls, saying in states like Madhya Pradesh and Rajasthan, the margin of defeat was small.
"Moreover, people have vented their ire against the governments that ruled the respective states for long. Now there is nothing that voters are going to hold against the NDA," Nitish Kumar said.