NORTH Korea has threatened the United States with "horrible disaster" after warships - including an aircraft carrier - visited a South Korean port.

"In this connection, the units of all services and army corps level of the Korean People's Army received an emergency order from its supreme command to reexamine the operation plans already ratified by it and keep themselves fully ready to promptly launch operations any time," a statement carried by the official KCNA news agency reads.



"The US will be wholly accountable for the unexpected horrible disaster to be met by its imperialist aggression forces' nuclear strike means...

"The US should bear in mind that the Korean people and army are highly alerted to promptly and confidently cope and foil blatant provocations of any hostile forces in the world with its own powerful military muscle."

The latest threat comes after an intense stand-off between the US and North Korea earlier this year was prompted by a series of military exercises in South Korea.

During the crisis, North Korea deployed a series of long-range missiles to hidden locations on its coast closest to Japan.

A little more than a month ago, news leaked from North Korea on how the former girlfriend of supreme leader Kim Jong-un had been "gunned down" after being arrested on pornography charges.

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North Korea has repeatedly defied international pressure to halt its nuclear weapons program, with fears that it now has enough weapons-grade plutonium to make up to 10 warheads.

The United States, which has almost 30,000 troops stationed in South Korea, says the presence of the USS George Washington carrier battle group was part of a "routine" port call.

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South Korean defence officials say the ships are taking part in an international maritime search and rescue exercise.

The most recent provocation from the despot state came in May when it fired a series of short-range missiles into the Sea of Japan. The launches followed a nuclear test in February which sparked a two-month standoff which put the region on high alert, including the deployment of advanced anti-missile defence systems.

During the crisis, North Korea's supreme military command said that The White House and Pentagon had been notified that "reckless operations'' using nuclear weapons had been approved.

"The moment of explosion is approaching fast,'' he said, warning that war could break out "today or tomorrow''.

US threats would be "smashed by... cutting-edge smaller, lighter and diversified nuclear strike means", the North Korean military said.

Originally published as 'Horrible disaster': Yes, Kim is back