Singh's election on Thursday became a formality after a third candidate Matang Singh, a former federal minister who had filed nomination as an independent contestant, withdrew from the race in favour of the prime minister.

The prime minister was elected unopposed from one of the two Rajya Sabha seats that fell vacant.

Matang Singh had joined the fray after ten members of Assam assembly belonging to Assam United Democratic Front led by Badruddin Ajmal backed his candidature.

Singh later claimed to reporters that he withdrew from contest following requests by several Congress leaders.

Although the Indian prime minister is from the northern state of Punjab, he has been a member of Rajya Sabha from Assam. While Lok Sabha members are elected directly by the people, members of Rajya Sabha are elected by members of the state legislatures.