North Korea’s military has threatened to reduce South Korea’s government "to ashes" amid escalating tensions between the two countries.

A statement released via the Korean Central News Agency (KCNA) threatened to “reduce all the rat-like groups and the bases for provocations to ashes in three or four minutes, (or) in much shorter time, by unprecedented peculiar means or methods of our style.”

The missive, issued by the Supreme Command of the Korean People's Army added: "Our revolutionary armed forces do not make an empty talk."

On Monday, UN Secretary General Ban Ki-moon urged North Korea to refrain from “further provocative measures”, warning such actions “will not be desirable for the peace and stability of the Korean peninsula,” AP reported.

North Korea also made threats of a “sacred war” following the South’s deployment of new long-range cruise missiles and alluded to perceived insults made against the “dignity of our supreme leadership.”

The statement added: "The indignation of the army and people of the DPRK (Democratic People's Republic of Korea) at the group of rat-like (South Korean President) Lee Myung Bak is running high.

"Shouts such as 'Destroy,' 'Beat to death' and 'Tear to death' are ringing out on this land. But the Lee group of traitors is still doing mischiefs, not coming to its senses."

A Seoul spokesman said: “We express deep concern that the North’s threats and accusations have worsened inter-Korean ties and heightened tensions.”

A further statement issued via KCNA on behalf of the Secretariat of the Committee for the Peaceful Reunification of Korea, accused Myung Bak of “seriously hurting the dignity of the supreme leadership” of the North.

It added: “The mischief made by rat-like Lee Myung Bak against them reminds one of a rabid dog barking towards the sky. What Lee uttered is no more than squeaks made by the rat before being killed by all people for its wrong doings.

“Now the army and people of the DPRK are shaking with towering indignation and anger and their resolution to wipe out the Lee group is running high.

“The revolutionary armed forces of the DPRK have already declared their special actions.

“The army and people of the DPRK will make rat-like Lee and his group meet the most miserable and disgraceful end for doing such mischief in rat holes as defaming the sun.”

The spat comes as Kim Jong Un takes steps to emulate his late father’s “military first” policy, with the 80th anniversary of the founding of the North Korean army taking place on Wednesday .

It also raises fears North Korea may be planning another provocation in the wake of its unsuccessful rocket launch earlier this month.

Two minutes after lift-off, the Unha-3 rocket reportedly exploded in flight and plunged into the Yellow Sea between mainland China and the Korean Peninsula.

Despite the failure, the launch drew international condemnation amid accusations from Washington, Tokyo and Seoul that the rocket, supposedly built to put a weather satellite in orbit, was in fact a ballistic missile test.

G8 foreign ministers meeting in Washington released a statement accusing the regime of violating UN Security Council resolutions.

The statement also called on the country to abandon its nuclear weapons and its "existing nuclear and ballistic missile programmes".

Click below for coverage of North Korea's failed rocket launch