A congress of the ruling party of North Korea has passed a resolution calling on the government to "boost the self-defensive nuclear force both in quality and quantity."
The congress -- the first in almost four decades -- on May 9 also adopted a decision to renounce the first use of nuclear weapons unless the country's sovereignty is impinged by another nuclear power.
The measures were adopted on the third day of the party congress, which is technically the supreme decision-making body in North Korea.
The United Nations imposed a new round of sanctions against North Korea in March after the country's fourth nuclear test in January and a long-range missile test in February.
