The Bharatiya Janata Party has overtaken the Congress to become the largest political party in the Rajya Sabha, where it now has 58 members against 57 of the main opposition party.
BJP MP Sampatiya Uikey, who was elected to the Upper House following a bypoll in Madhya Pradesh took oath on Thursday.
His election was necessitated by the death of Union Minster, Anil Madhav Dave.
This is the first time that the saffron party has become the number one formation in the Upper House after the Narendra Modi government came to power in May 2014.
The BJP-led National Democratic Alliance, however, is still short of a decisive majority in the house but the joining of Janata Dal-United to the ruling block has further boosted its numbers.
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