Aerial photo taken on June 4, 2020 shows the construction site of the Changling-Yongqing section of the China-Russia east-route natural gas pipeline in Youzha Township of Luanzhou City, north China's Hebei Province. (Xinhua/Yang Shiyao)

Aerial photo taken on June 4, 2020 shows the construction site of the Changling-Yongqing section of the China-Russia east-route natural gas pipeline in Youzha Township of Luanzhou City, north China's Hebei Province. (Xinhua/Yang Shiyao)

Aerial photo taken on June 4, 2020 shows the construction site of the Changling-Yongqing section of the China-Russia east-route natural gas pipeline in Youzha Township of Luanzhou City, north China's Hebei Province. (Xinhua/Yang Shiyao)

Aerial photo taken on June 4, 2020 shows the construction site of the Changling-Yongqing section of the China-Russia east-route natural gas pipeline in Youzha Township of Luanzhou City, north China's Hebei Province. (Xinhua/Yang Shiyao)

Aerial photo taken on June 4, 2020 shows the construction site of the Changling-Yongqing section of the China-Russia east-route natural gas pipeline in Youzha Township of Luanzhou City, north China's Hebei Province. (Xinhua/Yang Shiyao)

Aerial photo taken on June 4, 2020 shows the construction site of the Changling-Yongqing section of the China-Russia east-route natural gas pipeline in Youzha Township of Luanzhou City, north China's Hebei Province. (Xinhua/Yang Shiyao)