FILE PHOTO: North Korean leader Kim Jong Un attends the first day of the 8th Congress of the Workers' Party in Pyongyang, North Korea, in this photo supplied by North Korea's Central News Agency (KCNA) on January 6, 2021.      KCNA/via REUTERS/File Photo
North Korean leader Kim Jong-un attends the first day of the 8th Congress of the Workers’ Party in Pyongyang, North Korea. KCNA via Reuters

North Korea threatens to build more nuclear weapons over US 'hostility'