The two seats in Uttar Pradesh fell vacant after Chief Minister Yogi Adityanath and Deputy Chief Minister Keshav Prasad Maurya resigned from the Lok Sabha following their appointments last year.
The choice of Shukla is seen as an outreach by the party to Brahmins, who are the largest upper caste community in the state and have been its traditional supporters.
The party also announced its candidates in Bihar, naming Pradeep Singh as its nominee for the Araria Lok Sabha bypoll and Rinki Pandey for the Bhabua assembly byelection.
Singh, a former Araria MP, had lost to Rashtriya Janata Dal's Taslimuddin in 2014.
The byelections are scheduled to be held on March 11.
Photograph: PTI Photo
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