North Korea renewed its criticism of Japan over the releasing of "nuclear-contaminated" water into the sea from the crippled Fukushima nuclear plant in a speech Tuesday during a U.N. General Assembly session.

Kim Song, North Korea's ambassador to the world body, said in his address that Japan discharged the water in defiance of strong protests and criticism from the international community, "causing irrevocable damage to the safety of humanity and marine ecological environment."

Kim Song, North Korea's ambassador to the United Nations, delivers a speech during a U.N. General Assembly session in New York on Sept. 26, 2023. (Kyodo)

Japan began releasing treated radioactive water from the Fukushima Daiichi complex into the Pacific last month. The water was used to keep the plant's nuclear fuels cool after the facility was devastated by the major earthquake and tsunami in 2011.

Tokyo said the concentrations of tritium in the water have been kept lower than one-fortieth of the level specified by the country's safety standards, while the discharge plan is backed by the International Atomic Energy Agency, the U.N. nuclear watchdog. But China and North Korea have lashed out at the decision.

Kim also expressed his displeasure at recent discussions at the U.N. Security Council, saying it has taken up the issues of his country's human rights situation and launching of a satellite, but maintained "silence" over the Fukushima water discharge by Japan.

The envoy defended Pyongyang's development of nuclear weapons and ballistic missiles, saying North Korea "is urgently required to further accelerate the build-up of its self-defense capabilities to defend itself impregnably."

The United States, Japan, South Korea and other U.N. members have urged North Korea to suspend the nuclear and missile programs banned in past Security Council resolutions.

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