North Korea leader Kim Jong Un attends a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Soldiers march during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Soldiers march during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Fireworks explode over Pyongyang as a paramilitary parade is held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Fireworks go off during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Personnel in orange hazmat suits march during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

North Korea leader Kim Jong Un (R) attends a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

A general view of a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

A giant North Korean flag is unhurled during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Military equipments are paraded during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

North Korean soldiers attend a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS Image used for illustrative purpose

Military personnel take part in a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Fireworks explode over a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Artiliery goes off during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Soldiers march during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Soldiers march during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

North Korea leader Kim Jong Un (C) attends a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

Soldiers march during a paramilitary parade held to mark the 73rd founding anniversary of the republic at Kim Il Sung square in Pyongyang in this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS

North Korean leader Kim Jong Un takes part in celebrations to mark the 73rd founding anniversary of North Korea in Pyongyang this undated image supplied by North Korea's Korean Central News Agency on September 9, 2021. KCNA via REUTERS