South Korea on Friday signed a deal with US pharmaceutical giant Pfizer Inc. to buy 30 million doses of its COVID-19 vaccine to be administered next year, bringing the total amount to 60 million, health authorities here said.

The deal is a follow-up to an earlier deal signed in August that secured 30 million doses and had an option for an additional 30 million doses, according to the Korea Disease Control and Prevention Agency (KDCA).

The contract is part of South Korea's plan to secure enough vaccine doses to cover the first shots of the country's 52 million people next year, the KDCA said.

In June, the country began preparations to secure more vaccines for next year as the COVID-19 pandemic here is expected to continue even after achieving much-awaited herd immunity.

Since the country launched its vaccination program in late February, 76.1 percent of the population has been fully vaccinated and 80.6 percent received their first shots. (Yonhap)