United Nations Special Envoy for Syria Staffan de Mistura (on screen) briefs the Security Council by videoconference on the situation in Idlib at the UN headquarters in New York, Sept. 7, 2018. The UN special envoy for Syria said Friday that the situation there had all the "ingredients" for a "perfect storm" with devastating humanitarian consequences, urging all stakeholders to find a solution to avert a tragedy. (Xinhua/Li Muzi)