Kim Jong-un, top leader of the Democratic People's Republic of Korea, says his country will strive for world denuclearization and fulfill obligations of nuclear nonproliferation, the official KCNA news agency reported on Sunday.

Kim emphasized that the DPRK will not resort to nuclear weapons first unless its sovereignty is encroached upon by hostile forces with nuclear arms, the report said.

He made the remarks in a report delivered at a national congress of the ruling Workers' Party of Korea, the first in 36 years.