The team of the newly-elected East Delhi Municipal Corporation (EDMC) will also take charge today.
BJP's Patparganj councilor Bipin Bihari Singh will become deputy mayor in EDMC.
Mr Bhagat, who represents Geeta Colony ward, had defeated her AAP rival Pooja Chhabra by a margin of 2,869 votes in the high-stakes MCD polls held on April 23.
Last year, BJP's Satya Sharma, councilor from New Usmanpur, had trounced Congress rival Taj Mohammed for the post of mayor of east Delhi.
The saffron party has fielded its councilors Pravesh Sharma, Mr Santosh, Satpal Singh, Kiran and Kanchan Maheswari for the posts of members of the EDMC's standing committee, while AAP's Rekha Tyagi is in fray for the same.
After the election, the BJP, which had swept the civic polls, will have its mayors and deputy mayors in all the three civic bodies.
BJP had bagged 181 of the 270 wards in the polls. In the 64-member EDMC House, the BJP has 47 councilors, AAP 11, Congress three and BSP two.
Elections in two wards were postponed due to the death of candidates.
EDMC's Maujpur ward went to polls on May 14, while polling in NDMC's Sarai Pipal ward was held today. Results for both wards would be declared on May 23.
Get Breaking news, live coverage, and Latest News from India and around the world on NDTV.com. Catch all the Live TV action on NDTV 24x7 and NDTV India. Like us on Facebook or follow us on Twitter and Instagram for latest news and live news updates.