The MLAs will formally elect DMK chief MK Stalin as leader of the party to assume the chief minister's office.
The swearing in will be a low-key affair and held in the Raj Bhavan.
Governor Brig (retd) BD Mishra administered the oath of office and secrecy to Khandu and his ministerial colleagues at the swearing-in ceremony held in Itanagar.
Sidhu said former Indian prime minister Atal Bihari Vajpayee, who passed away yesterday, also talked about peace between the two countries.
The swearing-in ceremony on Wednesday saw the unlikeliest of political bigwigs come together.