The South Korean Yonhap news agency Sunday said that in the event of a likely attack from the North, Seoul was prepared to use intensive bombing to wipe the North Korean capital, Pyongyang, from the map.

"Every Pyongyang district, particularly where the North Korean leadership is possibly hidden, will be completely destroyed by ballistic missiles and high-explosive shells as soon as the North shows any signs of using a nuclear weapon. In other words, the North's capital city will be reduced to ashes and removed from the map," said the Yonhap source.

Information on the detailed bombing operation emerged after the South's Defense Ministry published the "Korea Massive Punishment and Retaliation" (KMPR) plan to the country's national assembly. The operation would particularly target leader Kim Jong Un and members of the upper echelons of government.

'Guardian angel'

While the South has no nuclear weapons of its own, it threatened to optimize the use of its conventional weapon arsenal. "The KMPR is the utmost operation concept the military can have in the absence of its own nuclear weapons," the source noted.

The South has developed a scenario in which it would mobilize its Hyanmoo ("guardian angel of the northern skies") surface-to-surface ballistic missile arsenal. The missiles, which are to be further developed and tested next year, have ranges of up to 1,000 kilometers (621 miles).

North scoffs at sanctions threat

A separate source told Yonhap that the military had launched a special operational unit dedicated to destroying the North Korean military leadership.

North Korea said on Sunday that an effort in the UN to ratchet up sanctions after its fifth and biggest nuclear test was "laughable."

The North on Friday detonated its most powerful nuclear explosion to date, saying it had developed the expertise to equip a ballistic missile with a warhead.

North Korea on Sunday restated an earlier demand that it should be recognized as a nuclear state, singling out US President Barack Obama in particular for criticism. The North says both missile and nuclear tests are necessary for it to address a US nuclear threat to its independence.

"Obama is trying hard to deny the DPRK's strategic position as a legitimate nuclear weapons state but it is as foolish an act as trying to eclipse the sun with a palm," said a Foreign Ministry statement quoted by the official KCNA news agency.