People watch a television news report showing pictures of US President Donald Trump (L) and North Korean leader Kim Jong Un at a railway station in Seoul on March 9, 2018. 
US President Donald Trump agreed on March 8 to a historic first meeting with North Korean leader Kim Jong Un in a stunning development in America's high-stakes nuclear standoff with North Korea. / AFP PHOTO / Jung Yeon-je
People watch a television report on a planned meeting between US President Donald Trump and North Korean leader Kim Jong-un, at a railway station in Seoul on March 9, 2018. Jung Yeon-je / AFP

Donald Trump and Kim Jong-un meeting: what happens next?