The United States will reportedly deliver four more F-35A fighter jets to South Korea this week.

According to military sources on Monday, the aircraft sent from the U.S. are scheduled to arrive at an air base in Cheongju, North Chungcheong Province on Thursday via Hawaii.

The arrival will bring the total number of the stealth fighters in the country's Air Force to eight. South Korea previously received a pair of F-35As on two occasions in March and July.

Another two are expected by the end of the year. South Korea has agreed to buy 40 F-35As in total, and the aircraft are expected to be fully delivered by 2021.