(161216) -- UNITED NATIONS, Dec. 16, 2016 (Xinhua) -- Retiring United Nations Secretary-General Ban Ki-moon (C) shakes hands with journalists after his End-of-Term press conference at the UN headquarters in New York, Dec. 16, 2016. UN Secretary-General Ban Ki-moon on Friday said that he will discuss with political leaders, close friends in South Korea on how best he can do for his home country after he steps down as the UN chief on Dec. 31, as the Asian country is facing "very difficult situation" and "the biggest challenge." Ban made the statement as he was asked at a press conference here whether he will run for the South Korean presidency after his retirement in five days. The press conference is his final one at the end of his two five-year terms as the UN secretary-general.(Xinhua/Li Muzi)