Tourists take photos at the Datang Everbright City scenic area in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Song Weiwei)

　　Tourists visit the Datang Everbright City scenic area in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Song Weiwei)

　　This photo taken on May 15, 2023 shows a view of a scenic moat area along the ancient city wall in Xi'an, northwest China's Shaanxi Province. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Zhang Bowen)

　　An electronic screen shows the information of the China-Central Asia Summit in Xi'an, northwest China's Shaanxi Province, May 16, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Shao Rui)

　　Tourists visit the Datang Everbright City scenic area in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Song Weiwei)

　　Tourists take photos with an installation of the China-Central Asia Summit in Xi'an, northwest China's Shaanxi Province, May 16, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Yibo)

　　This photo taken on May 15, 2023 shows a view of the Bell Tower in Xi'an, northwest China's Shaanxi Province. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Zhang Bowen)

　　Tourists visit the Datang Everbright City scenic area in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Song Weiwei)

　　Tourists visit the Datang Everbright City scenic area in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Yibo)

　　Tourists visit the Datang Everbright City scenic area in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Song Weiwei)

　　Tourists visit the Giant Wild Goose Pagoda scenic area in Xi'an, northwest China's Shaanxi Province, May 16, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Shao Rui)

　　Tourists visit the Tang Paradise in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Zhang Bowen)

　　This photo taken on May 16, 2023 shows a view of the Bell Tower in Xi'an, northwest China's Shaanxi Province. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Yibo)

　　Tourists take photos with an installation of the China-Central Asia Summit in Xi'an, northwest China's Shaanxi Province, May 16, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Yibo)

　　Tourists visit the Bell Tower in Xi'an, northwest China's Shaanxi Province, May 16, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Yibo)

　　This photo taken on May 15, 2023 shows a board displaying the information of the China-Central Asia Summit in Xi'an, northwest China's Shaanxi Province. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Zhang Bowen)

　　This photo taken on May 16, 2023 shows a view of the Bell Tower in Xi'an, northwest China's Shaanxi Province. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Yibo)

　　Tourists visit the Datang Everbright City scenic area in Xi'an, northwest China's Shaanxi Province, May 15, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Zhang Bowen)

　　People ride bikes on the ancient city wall in Xi'an, northwest China's Shaanxi Province, May 16, 2023. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Jing)

　　This photo taken on May 16, 2023 shows an installation of the China-Central Asia Summit in Xi'an, northwest China's Shaanxi Province. The China-Central Asia Summit is set to take place in Xi'an, the capital city of China's Shaanxi Province, on May 18 and 19. (Xinhua/Li Jing)