The President accepted the resignation of Ram Nath Kovind, as Governor of Bihar.
“The President of India is pleased to appoint Shri Keshari Nath Tripathi, Governor of West Bengal to discharge the functions of the Governor of Bihar, in addition to his own duties, until regular arrangements for the office of the Governor of Bihar is made,” a communiqué from the Rashtrapati Bhavan said.
The resignation follows his nomination as the ruling NDA's presidential candidate.
West Bengal Governor Keshari Nath Tripathi will discharge the functions of the Governor of Bihar, in addition to his own duties, it said.
The presidential election is scheduled for July 17. Mukherjee completes his five-year term on July 24.
The BJP yesterday announced the name of 71-year-old Kovind, a low-profile Dalit leader and a two-term BJP Rajya Sabha member, as its nominee for the president's post.
BJP president Amit Shah said Kovind hailed from Kanpur Dehat of Uttar Pradesh and described him as a person "from the Dalit community who has struggled to come up in life".
Shah, who was speaking after a meeting of the parliamentary board of the party, stressed the "poor and Dalit" factors many times during the announcement.
"Ramnathji had always worked for the Dalits and the backwards. Having been born in a poor family with a Dalit background, he struggled in life and today (Monday), the BJP parliamentary party has decided to make him the presidential candidate," Shah said.
The intention behind the pick, party leaders said, was clear in Shah's stress on the two words, "poor" and "Dalit".
They said the strategy behind the selection of Kovind was to checkmate the Opposition and send a message to the Dalits that the BJP stood by the deprived community.
The Opposition has called the announcement of Kovind's candidature "unilateral" and the Shiv Sena, the BJP's oldest ally, is yet to commit its support. But the NDA is said to be in control of enough votes to see its candidate through if a contest takes place.
RSS leaders privately welcomed the selection of Kovind, though the Bihar governor never had active connections with the Sangh. The RSS feels that Kovind's choice is in line with its agenda to bring "all the Hindus under one umbrella".
(With additional information from Agencies)