SOUTH KOREA/ NORTH KOREA (REUTERS) Locked and loaded in South Korea.

The military on Wednesday (Nov 29) responded within minutes to North Korea's latest missile test with a live-fire drill of its own.

The army, navy and air force all getting in on the action, launching three missiles at a single target near the border.

The message? "We are ready."

19th fighter wing 155th fighter squadron air force fighter pilot Kim Min Gi said: "Our military is closely monitoring North Korea's movements and is prepared to strike their core facilities at any point if they take action."

North Korea's official state media has revealed a handwritten note by Kim Jong Un, saying: "I order a test. Carry it out on Nov 29 at dawn. Fire it bravely for the Party and the motherland!"

Pyongyang said its powerful new intercontinental ballistic missile puts all of the US mainland within range.

It said the missile reached an altitude of 2,780 miles (4,473km), more than 10 times the height of the international space station - and that it travelled 600 miles (965km) during its nearly hour-long flight.

South Korea's President Moon Jae-In responded with a warning for Pyongyang, saying any threat of nuclear attack could spark a pre-emptive strike from the United States.