North Korea's elusive leader Kim Jong-un has placed the country's frontline troops on war footing following the exchange of fire between North and South Korea, media reports said Friday.

Kim has ordered the country's frontline forces to enter a state of war from 5 p.m local time (0830 GMT) on Friday, the official Korean Central News Agency (KCNA) reported, according to AFP. His declaration of a semi-state of war came late Thursday.

The North Korean autocrat, in an emergency meeting of the central military commission of the Workers Party of Korea, ordered the country's army to be well-armed to cope with any possible operations at any time, according to Xinhua news agency.

"The military commanders were urgently dispatched for operations to attack South Korean psychological warfare facilities if the South doesn't stop operating them," KCNA reported, according to Associated Press.

South Korea accused the North of firing across the demilitarized zone that separates the two Korean countries. North Korea's Korean People's Army, however, denied the allegations.

"Using the pretext that our forces fired one shell to the south, which is not true, it made reckless moves by firing 36 shells at our military posts," the North Korean army said in a statement, according to DW.

On Friday, South Korea blamed North Korea for denying its provocations and raised questions over its intension to hold inter-Korean dialogue.

"North's move is like covering up the heavens with one's palm," said Jeong Joon-hee, a Ministry of Unification spokesman, according to Yonhap news agency. "We cannot help having doubts about North Korea's sincerity over holding dialogue with South Korea."