N Korea: Developing long-range missiles 'in final stages'
Kim's address was monitored by South Korea's Yonhap news agency on Sunday.
Under Kim, who rose to power following his father's death in 2011, North Korea has seen steady progress in its nuclear and missile programmes, including two nuclear tests this year.
It recently claimed a series of technical breakthroughs in its goal of developing a long-range nuclear missile capable of reaching the continental United States.
UN resolutions call for an end to North Korea's nuclear and missile tests.
