The feud between Donald Trump and Kim Jong-un has taken yet another turn for the worst. After the leader of North Korea responded to Trump's "Rocket Man" insult, the president fired back [VIDEO] on social media.

Trump on Kim

It doesn't come as a surprise to many that Donald Trump has engaged in a war of words [VIDEO]with one of his critics. From the early days of the 2016 presidential election, the former host of "The Apprentice" made it part of his routine to hit back against those who opposed him. Whether it was in the Republican primary and his use of several nicknames to describe his opponents, like "low energy" Jeb Bush and "Little" Marco Rubio, to his attacks on the mainstream media and Hollywood celebrities, the billionaire real estate mogul has shown that he will not pull any punches regardless of the criticism he receives for doing so.

Last week, Trump took his feud with Kim Jong-un to another level, mocking the North Korean leader as "Rocket Man" during one of his many tweets. Trump used the nickname to bad mouth Kim again while addressing the United Nations General Assembly this past Tuesday, while also threatening to possibly "destroy" the country. In response, Kim released a statement on Thursday night where he ripped into Trump, calling him a "mentally deranged." As seen on his Twitter account on September 22, the president wasn't done with his attack.

Taking to his Twitter feed just before sunrise, Donald Trump responded to the latest rebuttal and statement by Kim Jong-un.

"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 tweeted out.

Twitter reacts

Not long after Donald Trump sent out his early morning tweet about Kim Jong-un, social media critics wasted no time in sounding off. "I would also consider you a mad man who doesn't mind starting a killing your citizens. That's what taking away healthcare is doing!" one tweet read.

"I simply think it's quite juvenile to have the sitting US president (arguably) engaging in name calling with other world leaders," one Twitter user added.

"t's really sad when most of the world actually agrees with Kim Jung Un about you. That's really saying something!" yet another tweet noted.

"Dear Mr Trump, stop. Just stop. Step down. U are going to get us all killed. Stop. I am begging you, stop," an additional tweet read. As the backlash continued, it showed that many Americans are worried about what could happen as a result of the name calling between Donald Trump and Kim Jong-un.