Chief Minister Conrad Sangma does not have to quit the post of MP to contest the by-poll in the state.
According to the Prohibition of Simultaneous Membership, 1950, a seat in Parliament can be vacated within 14 days from the date of election of the MLA.
Chief Electoral Officer Frederick Kharkongor said on Thursday that a Member of Parliament can still continue in office and contest the Assembly polls but ultimately he will have to quit one post.
The rule says a person has to become a member of the Assembly within six months from his date of election as the chief minister.
In the case of Conrad, he was sworn in as the chief minister on March 6, which means he will have to be elected as MLA before September 6.
The MPs who became chief ministers include Nitish Kumar (2005, Bihar), Shivraj Singh Chouhan (2005, MP), Mayawati (2007, UP), Mamata Banerjee (2011, West Bengal), Akhilesh Yadav (2012, UP) and Manohar Parrikar (2017, Goa).
NPP legislator from South Tura Agatha Sangma is expected to quit her seat to pave way for Conrad to contest the by-poll.
Sources said Congress legislator MM Danggo, who is set to join NPP, and Agatha are likely to resign on the same date sometime next month.