"We have decided not to take benefit of reservation to ensure that those who deserve it the most - the weaker among us - get it," the Hindustani Awam Morcha (HAM) president, who belongs to the Mahadalit caste, told the media in Patna.
Mr Manjhi said he and his family members will contest the next parliamentary and assembly elections in Bihar from general constituencies.
Mr Manjhi's statement comes in the wake of a top RSS leader's demand that the affluent sections among the scheduled castes should give up the benefit of quota in government jobs and educational institutions.
Mr Manjhi's HAM is an ally of the Bharatiya Janata Party-led National Democratic Alliance in Bihar.
Last week, HAM leaders had criticised the RSS statement disapproving of reservation demands by affluent sections and favouring a study to find if the backward classes were getting quota benefits.
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