DB Insurance, Hyundai Marine & Fire Insurance and Hana Insurance, said they will stop underwriting coal power projects.
DB Insurance added it will gradually retract its existing insurance coverage to operating coal plants, while the other two said they will keep their existing insurance coverage.
The confirmation follows pressure from a network of civic groups named Korea Beyond Coal, which has advocated for a complete coal phase-out in Korea by 2030.
In a statement on Tuesday, the network said the three major insurers, together with Hanwha General Insurance, had said they would no longer insure the construction and operation of new coal power projects.
Hanwha General Insurance could not immediately be reached for confirmation.
National Assembly member Lee So-young's office said the total coal underwritings by major South Korean insurers were around 59.2 trillion won ($52.18 billion), with Samsung Fire & Marine, DB Insurance and Hyundai Marine & Fire being the three biggest coal insurers.
Late last year, insurance affiliates of South Korea's biggest conglomerate Samsung Group, including Samsung Fire & Marine Insurance, pledged to step up their coal-free policies by banning investments in the coal industry.
($1 = 1,134.5600 won)
(Reporting by Joori Roh; editing by Barbara Lewis)
By Joori Roh