It is expected that President Trump and North Korean leader Kim Jong Un, according to South Korean officials, may meet by the end of May 2018 even if neither the date nor the place have been set yet.
Regarding the place could be Ulan Bator (Mongolia) or from the other side Sweden or Switzerland the latter is the only country known to Kim, he studied there under a pseudonym as a young man, in fact he never leaves North Korea to avoid attacks on his person or coups.