US President Donald Trump has continued his heated row with North Korean leader Kim Jong-un, saying his nuclear button is "much bigger" and "more powerful".
In a tweet sent in the early hours of this morning UK time, Trump rebuked comments made by Kim earlier in the week, saying his nuclear launch button was always on his table.
During a televised New Year's Day speech, Kim said: "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."
"This year we should focus on mass producing nuclear warheads and ballistic missiles for operational deployment," he added.
"These weapons will be used only if our security is threatened."
The comments are the latest in a tense back and forth between the two world leaders, with Kim calling Trump a "dotard", while Trump has previously branded Kim "Little Rocket Man".
The President has been vocal about stopping North Korea from having the capability to strike the US mainland with a nuclear-tipped missile, and has warned the US should not be underestimated.
"The United States has great strength and patience but if it is forced to defend itself or its allies we will have no choice but to totally destroy North Korea," Trump said last September.
North Korea meanwhile, has claimed it has nuclear weapons and could attack the US.