U.S. President Donald Trump, in his latest jab at North Korea's Kim Jong Un, taunted the isolated country's leader Sunday over his height and weight before pondering if the two could eventually be friends.

Trump tweeted from Hanoi on Sunday morning during his first visit to Asia as U.S. president and after North Korea blasted his speech in Seoul last week as "reckless remarks by a dotard," a colorful word employed by Pyongyang used to mean "old lunatic."

"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!" Trump wrote in a tweet.