North Korea's supreme leader Kim Jong-un has put his troops in a 'quasi-state of war' following an exchange of artillery along the border with South Korea on Thursday. 

Tensions between the Korean neighbours rose to dangerous levels on Thursday after North Korea allegedly shelled a border unit in South Korea in response to the latter's loudspeaker propaganda campaign along the border. 

South Korea responded by firing dozens of shells at North Korea.

Following the exchange of fire, Kim Jong-un convened an emergency meeting and ordered his troops to prepare for military action at the border. 

"Commanders of the Korean People's Army were hastily dispatched to the front-line troops to command military operations to destroy psychological warfare tools if the enemy does not stop the propaganda broadcast within 48 hours and prepare against the enemy's possible counteractions,"  North's Korean Central Television reportedly said, according to South Korea's news agency Yonhap. 

The war-preparedness by North came after a stern warning was sent to South Korea on Thursday, in which it warned of military action if the loudspeaker campaign is not stopped in 48 hours. 

The skirmish had led South Korea to immediately evacuate its civilians from along the western border where the shelling took place. 

South Korea had launched the loudspeaker propaganda last week as part of a psychological warfare technique after it claimed that North Korean landmines wounded some of its soldiers at the border.

North Korea and South Korea remain in a state of war as the two countries did not sign a peace treaty during the partition in 1953 and ended the 1950-53 Korean war with a ceasefire.