Reuters--  In his tweet he also said Chinese President Xi Jinping was "upping sanctions" on North Korea in response to its nuclear and missile programs and that Xi wants Pyongyang to "denuclearize."

On Sunday morning while on a trip to Asia, Trump tweeted "Why would Kim Jong-un insult me by calling me 'old,' when I would NEVER call him 'short and fat?' Oh well, I try so hard to be his friend - and maybe someday that will happen!"