The Bharatiya Janata Party on Sunday announced an alliance with prominent OBC (Other Backward Class) leader Upendra Kushwaha’s political outfit Rashtriya Lok Samata Party (RLSP) in Bihar.

State BJP president Mangal Pandey said the RLSP will be a new arm of the National Democratic Alliance (NDA) and will contest three seats in Bihar.

Mr. Kushwaha, who belongs to the OBC Koeri caste, quit the ruling Janata Dal (United) and resigned as its Rajya Sabha MP, in December 2012, following differences with Bihar Chief Minister Nitish Kumar. The OBC and EBC (Extremely Backward Class) form a key vote base of Mr. Kumar’s JD (U).

“The countdown to Mr. Kumar’s downfall has begun. He insulted the mandate on which his politics is based and he takes pride in. He bit the hand that fed him. This alliance will have an impact in the Lok Sabha polls,” Mr. Kushwaha said at a joint press conference of the BJP and RLSP.

Mr. Kushwaha floated the RLSP in March 2013, before the JD (U)-BJP split. At the time of launching his party in Patna, he had said that his party would work towards ousting the NDA from Bihar.

On Sunday, however, he cited Gujarat CM and BJP’s CM candidate Narendra Modi’s vision for farmers and labourers as the reason for joining the BJP. “We stand for social justice. This is the first time an OBC person [Mr. Modi] is close to becoming the PM.”

The BJP and RLSP will together contest 40 Lok Sabha seats in Bihar, their leaders have said. Mr. Kushwaha will also support the BJP’s ‘rail roko’ campaign on the issue of special status.

The BJP said there was no decision yet on which three seats the RLSP would be contesting.