“I will make the man holding the prerogative of the supreme command in the U.S. pay dearly for his speech,” Kim said in a statement released by the official Korean Central News Agency, which also published a photo of the North Korean leader sitting at his desk holding a piece of paper.

“I am now thinking hard about what response he could have expected when he allowed such eccentric words to trip off his tongue. Whatever Trump might have expected, he will face results beyond his expectation,” Kim said, saying that he would “tame” Trump “with fire.”

On Friday, Trump added the latest barb with a tweet calling Kim a “madman” who brings famine and death on North Koreans.

“Kim Jong Un of North Korea, who is obviously a madman who doesn’t mind starving or killing his people, will be tested like never before!” Trump wrote.