UPPL chief Promod Boro, who has been named as the new chief executive member (CEM) of the Bodoland Territorial Council (BTC), will take oath on Tuesday in Kokrajhar.
The oath-taking ceremony will be held at Bodofa Nagar in Kokrajhar at 10 am on Tuesday.
Assam chief minister Sarbannanda Sonowal, finance minister Himanda Biswa Sarma and several other top BJP leaders will attend the oath-taking ceremony.
Earlier on Sunday, Assam governor Jagdish Mukhi accepted the claim of the UPPL-BJP-GSP to form the new council.
The UPPL, which won 12 seats in just-concluded BTC polls, has formed an alliance with the BJP and Gana Suraksha Party (GSP).
While the BJP managed to get nine seats, Kokrajhar MP Naba Sarania-led GSP captured just one seat.
The BTC administration has declared a local holiday in four BTR districts on Tuesday for the oath-taking ceremony.
The principal secretary of BTC on Monday issued an order declaring December 15 as a local holiday for the oath-taking ceremony of newly elected members of BTC.
The government offices will remain closed in Kokrajhar, Chirang, Baksa and Udalguri districts.
Meanwhile, massive preparations are going on at Green Field in Kokrajhar for the oath-taking ceremony.