Incoming UN Secretary-General Antonio Guterres will take the oath of office on Monday, hoping to show he is primed for action despite anxiety over the US role in the world under unpredictable Donald Trump. During a formal ceremony at the General Assembly, Guterres will be sworn in before outlining in an address to all 193 UN member-states his plans to confront global crises and reform the 71-year-old United Nations. The first former head of government at the UN helm, Guterres will take over from Ban Ki-moon on January 1, just weeks before President-elect Trump moves into the White House.