Japanese Prime Minister Shinzo Abe takes off his face mask at the start of a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe has said at a press conference on Friday that he will step down from his post due to health concerns. (Photos: Xinhua)

An electronic screen shows that Japanese Prime Minister Shinzo Abe speaks at a press conference in Tokyo, Japan, on Aug. 28, 2020. Japanese Prime Minister Shinzo Abe has said at a press conference on Friday that he will step down from his post due to health concerns.

Japanese Prime Minister Shinzo Abe reacts during a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe has said at a press conference on Friday that he will step down from his post due to health concerns.

Japanese Prime Minister Shinzo Abe bows during a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe has said at a press conference on Friday that he will step down from his post due to health concerns.

Japanese Prime Minister Shinzo Abe reacts during a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe has said at a press conference on Friday that he will step down from his post due to health concerns.

An electronic screen shows that Japanese Prime Minister Shinzo Abe speaks at a press conference in Tokyo, Japan, on Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

Japanese Prime Minister Shinzo Abe takes off his face mask at the start of a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe has said at a press conference on Friday that he will step down from his post due to health concerns.

An electronic screen shows that Japanese Prime Minister Shinzo Abe speaks at a press conference in Tokyo, Japan, on Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

Japanese Prime Minister Shinzo Abe takes off his face mask at the start of a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

Electronic screens show that Japanese Prime Minister Shinzo Abe speaks at a press conference in Tokyo, Japan, on Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

Japanese Prime Minister Shinzo Abe speaks during a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

An electronic screen shows that Japanese Prime Minister Shinzo Abe speaks at a press conference in Tokyo, Japan, on Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

An electronic screen shows that Japanese Prime Minister Shinzo Abe speaks at a press conference in Tokyo, Japan, on Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

Photo taken on Aug. 28, 2020 shows the Prime Minister's Office in Tokyo, Japan. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.

Japanese Prime Minister Shinzo Abe takes off his face mask at the start of a press conference in Tokyo, Japan, Aug. 28, 2020. Japanese Prime Minister Shinzo Abe said at a press conference Friday that he would step down from his post due to health concerns.