MISC, through its subsidiaries Polaris LNG Three Pte Ltd and Polaris LNG Four Pte Ltd, have also signed an agreement to build the carriers in South Korea, it said in a statement.
The 174,000-cubic meter LNG carriers will be chartered for 10 years by Exxon Mobil unit, SeaRiver Maritime LLC (SRM).
"The agreement brings the total number of contracts with SRM to four LNG carriers," MISC said, adding that it had previously signed 15-year time charter contracts with SRM in 2019.
The vessels being built in South Korea are set for delivery in the first quarter of 2023.
(Reporting by Emily Chow; Editing by Savio D'Souza)