LONDON — North Korean officials on Monday said the country’s status as nuclear state “has become irreversible,” despite efforts by the West to negotiate an end to the production of those weapons, according to state media.

“The position of the Democratic People’s Republic of Korea as a nuclear weapons state which has been permanently specified in the supreme and basic law of the state has become irreversible,” North Korea’s Permanent Mission to the U.N. said in a press statement, according to the Korean Central News Agency.

The International Atomic Energy Agency, the intergovernmental body for nuclear cooperation, has no “legal right and moral justification” to interfere with what North Korea consider an “internal affair,” the mission’s press statement said.

The statement on Monday coincided with the launch of Freedom Edge 25, a joint military exercise being held by the United States, South Korea and Japan, off South Korea’s Jeju Island. Those drills are scheduled to run through Sept. 19.

North Korea’s Pak Jong Chon, vice-chairman of the Central Military Commission, said on Sunday that those drills “pose a grave challenge to the security interests of our state and a major danger of undermining regional stability and escalating military tension,” according to state media.

The secretive state on Monday accused the United States of violating its own stated obligation of preventing nuclear proliferation “while concentrating more than anyone else on nuclear power buildup.”

“The U.S. has gone to extremes in its nuclear threat as days go by and the U.S.-led nuclear alliance is getting desperate in its confrontational moves,” the North Korean officials said on Monday.

IAEA Director General Rafael Mariano Grossi earlier this month pointed to North Korea’s nuclear development programs as “clear violations” of U.N. Security Council resolutions.

He said his agency nonetheless “continues to maintain its enhanced readiness to play its essential role in verifying the DPRK’s nuclear program.”

ABC News’ Will Gretsky contributed to this report.