The leaders of North Korea and China have vowed to further develop bilateral ties in messages traded on the 60th anniversary of their treaty of friendship.

The North's official Korean Central News Agency (KCNA) on Sunday unveiled the messages exchanged by its leader Kim Jong-un and Chinese President Xi Jinping to celebrate the 1961 signing of the treaty of friendship, cooperation and mutual assistance.

In the message to Kim, Xi reportedly said that he is willing to strengthen strategic communication with Kim and continue to develop the friendly and cooperative relations of their nations to bring greater happiness to their countries and their people.

Kim also stressed the importance of close ties and cooperation between the two nations, saying that it is the firm stance of the North's Workers' Party and the government to ceaselessly develop the friendly and cooperative relations between the North and China.

Kim emphasized that the treaty is showing stronger vitality in ensuring peace and stability in Asia and the world when the hostile forces have become more desperate in their challenges and obstructive moves.