He made public such celebrated works as "Let Us Carry Out the Great Leader Comrade Kim Il Sung's Instructions for National Reunification" and "Let Us Reunify the Country Independently and Peacefully through the Great Unity of the Entire Nation" to indicate the ways for the country's reunification. And he formulated as the three charters for national reunification the three principles of national reunification, the ten-point programme for great national unity and the proposal for founding the Democratic Federal Republic of Koryo set forth by President Kim Il Sung.

To bring earlier the national reunification, he provided a historic north-south summit in Pyongyang in Juche 89 (2000), at which the June 15 North-South Joint Declaration was adopted. The adoption of the joint declaration made it possible for all Koreans to dynamically advance toward the country's reunification in the idea of "By our nation itself".

Multi-faceted contacts and dialogues, including ministerial talks, gained momentum between the north and the south of Korea, while roads and railways, severed for decades, were reconnected and air and sea routes opened.

In October 2007 another inter-Korean summit took place in Pyongyang, at which the Declaration for Development of North-South Relations and Peace and Prosperity was adopted. The event was attributable to the devoted efforts made by Kim Jong Il.

The Korean people praise him as the sun of the nation as he established the principle of keeping independence in the movement for national reunification and ushered in a new era of national independence and reunification with his unique idea and distinguished guidance.

Kim Jong Il's patriotic devotion and feats for national reunification will remain in the history of the nation forever.