Maimunah Mohd Sharif, Executive Director of UN-Habitat, speaks at a press conference on the sideline of the High Level Political Forum on Sustainable Development at the UN headquarters in New York, on July 11, 2018. The world's population living in cities or urban centers has risen steadily over the years, poised to reach 60 percent of the entire population by 2030 and 66 percent by 2050, a UN-Habitat report said Wednesday. (Xinhua/Li Muzi)