"All the 22 MLAs of Sikkim Democratic Front had a meeting and we have unanimously decided to elect Pawan Chamling as our leader. We will form the government on Wednesday," SDF Vice-President K B Chamling told PTI.
Last week, SDF won the assembly polls by a two-third majority with 22 of its MLAs being elected to the 32 member House.
After this swearing-in, he will be on way to surpass the record of former West Bengal chief minister Jyoti Basu of being the longest serving chief minister of the country.
Basu had ruled West Bengal for 23 years from 1977 to 2000.