Apparently, when it comes to nuclear buttons, size matters.

A day after North Korean leader Kim Jong Un said that he has a button ready to launch nuclear weapons installed in his desk, President Trump tweeted that he, too, has a nuclear button, "but it is a much bigger & more powerful one than his, and my Button works!"

Trump's tweet was apparently in response to a speech Monday in which Kim said, “The United States should know that the button for nuclear weapons is on my table,” according to a translation by the Associated Press.

More: Kim Jong Un says he has complete nuclear arsenal and a button on his desk

The exchange over nuclear buttons continues an ongoing war of words between the two leaders, as the world anxiously worries that the bombastic back-and-forth could quickly develop into military hostilities.

Trump has repeatedly referred to Kim as "Rocket Man" and "Little Rocket Man." He has also called Kim a "sick puppy," a "madman," and "short and fat." Kim has called Trump a "mentally deranged dotard."

The Trump administration has imposed harsher sanctions on North Korea and pressured China to do more to help rein in Kim's regime, but so far no of those efforts have succeeded it ending North Korea's continued efforts to become a nuclear power.

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