MP Rajiv Ranjan, better known as Lalan Singh, was on Saturday chosen as its national president at the party's national executive meeting here, sources said.
Singh replaces R C P Singh, who offered to step down as he has been inducted as a Cabinet minister in the Modi government.
Lalan Singh, a Bhumihar MP from Munger Lok Sabha constituency in Bihar, has long been a close confidant of Bihar Chief Minister Nitish Kumar, the main face of his party.
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