North Korea Warns South Of Final Destruction

North Korea has threatened South Korea with "final destruction" during a debate at the United Nations Conference on Disarmament.

"As the saying goes, a newborn puppy knows no fear of a tiger. South Korea's erratic behaviour would only herald its final destruction," North Korean diplomat Jon Yong Ryong told the meeting.

Mr Jon's comments drew quick criticism from other nations, including South Korea, France, Germany and Britain, whose ambassador Joanne Adamson said such language was "completely inappropriate".

"It cannot be allowed that we have expressions which refer to the possible destruction of UN member states," she said.

Spanish Ambassador Javier Gil Catalina said the comment appeared to be a breach of international law.

"In the 30 years of my career I've never heard anything like it and it seems to me that we are not speaking about something that is even admissible, we are speaking about a threat of the use of force that is prohibited by Article 2.4 of the United Nations charter," Mr Catalina said.

North Korea tested a nuclear bomb last week in defiance of UN resolutions.

Since then the country's southern neighbour has warned it could strike the isolated state if it believed an attack was imminent.

Pyongyang said the aim of the test was to bolster its defences given the hostility of the United States, which has led a push to impose sanctions on North Korea.

"Our current nuclear test is the primary countermeasure taken by the DPRK (North Korea) in which it exercised its maximum self-restraint," said the North Korean diplomat Mr Jon.

"If the US takes a hostile approach toward the DPRK to the last, rendering the situation complicated, it (North Korea) will be left with no option but to take the second and third stronger steps in succession," he said.

North Korea has already told key ally China that it is prepared to stage one or two more tests this year to force the United States into diplomatic talks.

US Ambassador Laura Kennedy said she found North Korea's threat profoundly disturbing and later tweeted that it was "offensive".

Washington and its allies are believed to be pushing to tighten the noose around North Korea's financial transactions in a bid to starve its leadership of funding.