Washington prepared to take 'devastating' military action against North Korea: US President Donald Trump

US President Donald Trump says Washington is "totally prepared" to take a “devastating” military action against Pyongyang as rhetoric heats up between the two countries following the recent spate of tit-for-tat barbs.

“We are totally prepared for the second option, not a preferred option,” Trump said at a White House news conference on Tuesday, referring to military force. “But if we take that option, it will be devastating, I can tell you that, devastating for North Korea. That’s called the military option. If we have to take it, we will.”

"He's acting very badly," Trump said of North Korea's leader Kim Jong-un. "He's saying things that should never ever be said."

The US president also said that the North Korean crisis could have been dealt with in the past, blaming "past administrations" for not taking action.

"North Korea should have been handled 25 years ago, 20 years ago, 15 years ago, 10 years ago, five years ago, and it could have been handled more easily," Trump said. "You have various administrations, which left me a mess. But I'll fix the mess. So we will see what happens with North Korea."   

The remarks came days after the US president threatened to “totally destroy” North Korea during his first address to the United Nations General Assembly. Trump also called the North Korean leader a “rocket man” who is “on a suicide mission.”

Kim followed up by calling Trump a "dotard" – a phrase used to describe an elderly, senile person – and a "frightened dog."

Pyongyang announced on Monday that Trump had declared war on North Korea and that it reserved the right to take countermeasures. North Korea also threatened to down US bombers dispatched to the Korean Peninsula over the weekend even if they were not in its airspace.

"Since the United States declared war on our country, we will have every right to take countermeasures including the right to shoot down US strategic bombers even when they are not yet inside the airspace border of our country," said Ri Yong-ho, North Korea's foreign minister. "The question of who won't be around much longer will be answered then."

In this handout image provided by South Korean Defense Ministry, US Air Force B-1B Lancer bombers flying with F-35B fighter jets and South Korean Air Force F-15K fighter jets during a training run at the Pilsung Firing Range on September 18, 2017 in Gangwon-do, South Korea.

The renewed tensions come as military maneuvers were being held by US bombers over waters east of North Korea. The Pentagon said its bombers from Guam and Okinawa, in Japan, had flown in international airspace over the waters in “a clear message that the president has many military options to defeat any threat.”

North Korea, which conducted its sixth and most powerful nuclear weapon test earlier this month, has threatened to conduct another nuclear test, and has said that they have considered doing so in the Pacific Ocean.

North Korea is under mounting international pressure over its missile and military nuclear programs and has been subjected to an array of sanctions by the United Nations. However, Pyongyang says it needs to continue and develop the programs as a deterrent against hostility by the US and its regional allies, including South Korea and Japan.