A beaming BJP President Rajnath Singh made this announcement at a news conference at his residence after another round of hectic parleys by the leaders of the two parties on seat-sharing in Bihar ahead of the Lok Sabha elections.
Singh said the BJP will contest the remaining 33 seats in Bihar.
"I have complete faith that this alliance between the BJP and the LJP will benefit NDA not only in Bihar but also in other states in the country," he said.
He noted that Paswan was joining the BJP-led alliance days after Dalit leader and RPI Chief Ramdas Athavale became part of NDA and another Dalit activist Udit Raj joined the saffron party.
Singh said Paswan will meet party patriarch L K Advani and BJP prime ministerial candidate Narendra Modi in the next few days. The LJP supremo will also share the dais with Modi at the latter's rally on March 3 in Muzaffarpur in Bihar.
Paswan exuded confidence that the next government will be formed by the National Democratic Alliance.
"Next government will be a NDA govt," he said.
"You will ask me about Modi. As far as Modi ji is concerned, LJP is now a part of NDA and NDA has already declared Modi as its PM candidate, he added.
Paswan parted ways with BJP by resigning as coal minister from the NDA government in April 2002, citing Gujarat riots when Modi was the chief minister.
Noting that he had already been a part of NDA, Paswan said that the kind of work which had been done by NDA for poor and backwards had not been done in the last few years.
Paswan said that as far as minorities were concerned, it was a "commitment" and asserted that the way Rajnath Singh had spoken two days ago was praiseworthy.
Paswan was apparently referring to Rajnath Singh's comments in which he had while reaching out to Muslims ahead of Lok Sabha elections said that "whenever, wherever if there has been any mistake and shortcoming on our part, I assure you that we will apologise to you by bowing our heads."
Paswan also said that Modi had himself said that he was a "victim of untouchability" and had been ridiculed as a tea seller.
Rajnath Singh said that the joining of new parties in NDA signified that not just dalit leaders but dalit sections of the society were also looking forward to Modi becoming the prime minister.
Paswan praised Singh saying that the NDA which had shrunk was expanding under his leadership.
Earlier in the day, in a politically-significant gesture, BJP leaders Rajiv Pratap Rudy, Ravi Shankar Prasad and Shahnawaz Hussain went to Paswan's residence to hold consultations with him.
Soon after, Bihar LJP President Pashupati Kumar Paras and party Parliamentary Board Chairman Chirag Paswan met BJP leaders Dharmendra Pradhan, Bihar BJP chief Mangal Pandey, its leader in state assembly Nand Kishore Yadav and senior leader Sushil Kumar Modi.
Rudy, Hussain and Prasad were also present in the meeting.
From the LJP side, Chirag and Paras negotiated the alliance with BJP after LJP Secretary General Abdul Khalik took a back seat after talks with Congress-RJD failed.
Significantly, the meetings between the two parties are taking place on a day BJP's prime ministerial candidate Narendra Modi is here and there was speculation that Paswan would meet him.
Modi held a separate meeting with BJP chief Rajnath Singh.
The meeting came a day after LJP gave clear hints about allying with BJP after their Parliamentary Board meeting.
After meeting Paswan, Ravishankar Prasad said the LJP chief is a "senior" leader not only of Bihar but the entire country.
"We have worked together during the Atal Bihari Vajpayee government," the BJP leader recalled.
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