North Korea's leader Kim Jong-un delivers a speech during his visit to Kim Jong Un University of National Defense to celebrate the 60th anniversary of its founding, in this photo provided by North Korea's official Korean Central News Agency, Oct. 8. Yonhap

North Korean leader Kim Jong-un has threatened to use nuclear weapons if the country's enemies attempt to use armed force against it, state media reported Tuesday.

The latest rhetoric comes as North Korea is presumed to have kicked off a key parliamentary meeting Monday to revise the constitution in a way that cements its animosity toward South Korea as a "primary foe."

"All military force will be used without hesitation if enemies attempt to use force against our country, and the use of nuclear weapons will not be ruled out," Kim said in a speech during his visit to Kim Jong Un University of National Defense on Monday, according to the Korean Central News Agency.

Kim said the country's constitution will "give a stern order to the military' to take actions, if provoked," without elaborating.

The warning came six days after South Korean President Yoon Suk Yeol said that North Korea will face the end of its regime if it attempts to use nuclear weapons, warning of a "resolute and overwhelming" response from the South Korea-U.S. alliance.

Kim later called Yoon an "abnormal man" for talking about military actions against the nuclear-armed North Korea.

The North's leader said North Korea will accelerate its move to become a military and nuclear superpower in a bid to bolster its nuclear deterrence.

"At a time when the South Korea-U.S. alliance has completely been transformed into a nuclear alliance, as they advertised, our nation's nuclear response posture should be completed to a height that does not have any limit," he noted.

North Korea disclosed a clandestine nuclear uranium enrichment facility for the first time last month in an apparent bid to show that Pyongyang has no intention of giving up its nuclear arsenal.

Tensions on the Korean Peninsula run high, as North Korea has launched trash-carrying balloons toward the South in retaliation for anti-Pyongyang leaflets sent across the border by North Korean defectors and activists in South Korea.

In response, South Korea's military has been blasting daily anti-Pyongyang propaganda broadcasts through its loudspeakers along the border since July 21.

In the speech, the North's leader also reaffirmed his stance that South and North Korea are "two states hostile to each other."

"Previously, we talked about liberation of the southern side or unification by force. But we have no interest in it and since we've declared the two separate states stance, we have never been conscious of that country," he said.

"We have no intention of attacking the Republic of Korea. It is creepy to even be conscious of that country and we don't want to face them," Kim added.

Experts said Kim's speech indicates North Korea could formalize its nuclear force policy and his "two hostile states" stance in a revised constitution.

"It is very symbolic that Kim visited the university on the opening day of a Supreme People's Assembly session," Hong Min, a senior research fellow at the Korea Institute for National Unification, said.

Citing Kim's warning that the enemies should not annoy the North, Hong said North Korea could codify its territorial clauses in an "offensive" manner, including the maritime border.

At a year-end party meeting in December, the North's leader defined inter-Korean ties as those between "two states hostile to each other" and said there is no point in seeking reconciliation with South Korea.

He later called for revising the constitution in a way that removes unification-related clauses and enshrines the commitment to subjugate South Korean territories in the event of war.

Kim's visit to the university, known as a key academy designed to nurture talent in the munitions industry, was meant to celebrate the 60th anniversary of its establishment.

Jon Il-ho, president of the university, has been under U.S. sanctions over his role in the development of weapons of mass destruction and ballistic missiles. (Yonhap)