Donald Trump
Donald TrumpReuters

U.S. President Donald Trump was unfazed on Tuesday by North Korean leader Kim Jong Un’s threat that he has a nuclear launch button on his desk.

“North Korean Leader Kim Jong Un just stated that the ‘Nuclear Button is on his desk at all times.’ Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger & more powerful one than his, and my Button works!” tweeted Trump.

The North Korean leader claimed on Sunday that his country has developed the capability to hit the entire U.S. mainland with its nuclear weapons.

“The entire United States is within range of our nuclear weapons, and a nuclear button is always on my desk. This is reality, not a threat,” Kim said in a televised New Year’s Day speech.

He also claimed that "we have secured powerful deterrence against the nuclear threat from the U.S. and said the U.S. should be aware that his country's nuclear forces were now a reality not a threat, and North Korea achieved the historic feat of "completing" its nuclear forces.

The isolated country has continued to carry out missile and nuclear tests, in defiance of international pressure and United Nations resolutions.

Kim’s threats were the latest in an ongoing back-and-forth between he and Trump, who refers to Kim as “little rocket man” and has in the past threatened to "totally destroy" North Korea if it attacks the United States.

North Korea recently launched a Hwasong-15 missile, a new type of intercontinental ballistic missile (ICBM) which officials said can fly over 13,000 km (8,080 miles).

Pyongyang said following that launch as well that that it had test-fired its most advanced missile, putting the U.S. mainland within range, and also declared itself to be "a responsible nuclear power".

The United Nations Security Council recently announced new sanctions in response to North Korea’s November 29 test. Those sanctions sought to further limit North Korea’s access to refined petroleum products and crude oil and its earnings from workers abroad.

The U.S. later followed and slapped sanctions on two North Korean officials behind their country’s ballistic missile program.