North Korean leader Kim Jong Un vowed at ruling party congress not to use nuclear weapons unless its sovereignty is violated, South Korean media reported Sunday, citing the North's media.
Kim added that Pyongyang would make efforts to promote global non-proliferation, the Yonhap news service said, citing an ongoing seventh Workers' Party congress.
The long-anticipated congress, the first since 1980, nominated Kim for the top party post earlier.
On Friday, he hailed the country's successful nuclear test and satellite launch, "boosting the country's dignity and national power."
Tensions on the Korean Peninsula escalated after North Korea carried out a nuclear test - allegedly a hydrogen bomb test - in early January and put a satellite into orbit a month later which violated UN Security Council resolutions and triggered condemnation from the international community.
In March, the UN Security Council unanimously adopted Resolution 2270, which severely restricted Pyongyang's engagement in commercial activities that could benefit its nuclear or missile programs.