Two-time Mizoram Chief Minister Zoramthanga will tender his resignation to Governor Lieutenant General Madan Mohan Lakhera at 3 pm following the defeat of his Mizo National Front, the sources said.
The Congress has already secured the required 21 seats to form the government in the 40-member House.
The chief minister was defeated in his Champhai North seat and the MNF has so far manage to win only one seat.