Outgoing UN Special Envoy for Syria Staffan de Mistura speaks to journalists during a press encounter after a Security Council meeting on Syria, at the UN headquarters in New York, Dec. 20, 2018. UN Special Envoy for Syria Staffan de Mistura on Thursday received a standing ovation in the Security Council as he bid farewell. De Mistura, after four years and four months in the job, will step down by the end of the year and he will be replaced by Geir Pedersen of Norway. (Xinhua/Li Muzi)