North Korea adopted a constitutional amendment to incorporate its policy of "rapidly developing nuclear weapons to a higher level" during a key parliamentary session earlier this week, with leader Kim Jong Un stressing the need to deter U.S. military "provocations," state-run media said Thursday.

At the two-day session of the Supreme People's Assembly through Wednesday, Kim said, "We must neither change nor concede the present position of our country as a nuclear weapons state, but, on the contrary, continue to further strengthen the nuclear force," the official Korean Central News Agency reported.

Undated photo shows the Supreme People's Assembly during its two-day session from Sept. 26, 2023, at the Mansudae Assembly Hall in Pyongyang. (KCNA/Kyodo)

The incorporation of the policy to bolster its nuclear force in the supreme law was "the most just and reasonable crucial step," Kim added, referring to the importance of accelerating the modernization of the country's nuclear weapons to "hold the definite edge of strategic deterrence" against the United States, KCNA said.

Kim said the establishment of "the triangular military alliance" involving the United States, South Korea and Japan had finally resulted in the emergence of an "Asian-version NATO," which he described as "the worst actual threat."

He also criticized Washington for having "maximized its nuclear war threats" to North Korea by conducting large-scale military drills and deploying its strategic nuclear assets near the Korean Peninsula on a permanent basis, the report said.

The constitutional amendment came about a year after Pyongyang authorized the pre-emptive use of nuclear weapons in a new law at a parliamentary session and stated that the country's status as a nuclear weapons state has become "irreversible."

In a constitutional change in April 2012, North Korea proclaimed its status as a nuclear power.

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