UN Secretary-General Antonio Guterres warned Friday that the world is living in the shadow of nuclear catastrophe, fueled by growing distrust and tensions between the nuclear powers.

Iran PressAmerica: The UN chief told a high-level meeting to commemorate the recent International Day for Total Elimination of Nuclear Weapons that progress on ridding the world of nuclear weapons “has stalled and is at risk of backsliding."

He said strains between countries that possess nuclear weapons “have increased nuclear risks.”

Guterres has expressed deep concern at the escalating disputes between the Trump administration and China. Relations between the US and Russia are at a low point. Nuclear-armed India and Pakistan are feuding over Kashmir, and India just had a border skirmish with China. And North Korea boasts about its nuclear weapons.

Without naming any countries, Guterres said programs to modernize nuclear arsenals “threaten a qualitative nuclear arms race,” not to increase the number of weapons but to make them “faster, stealthier and more accurate.”

Guterres also pointed to the only treaty constraining the size of the world’s largest nuclear arsenals -- the New Strategic Arms Reduction Treaty between the United States and Russia -- which is set to expire next year.

“It is imperative” that the two countries extend it without delay for the maximum five years, he said, warning that without a treaty there is an “alarming possibility of a return to unconstrained strategic competition.”

The secretary-general said the nuclear non-proliferation treaty or NPT, which marks its 50th anniversary this year, remains the cornerstone of nuclear disarmament and efforts to prevent the spread of nuclear weapons.

The five-year review of its implementation was postponed because of the COVID-19 pandemic until next year and Guterres urged its 191 parties to use the extra time to strengthen the treaty, including making “tangible progress towards the elimination of nuclear weapons."

Guterres said he also looks forward to the entry into force of the first-ever treaty to ban nuclear weapons, which was adopted in July 2017 by 122 countries. Once it has 50 ratifications, the treaty will enter force in 90 days, and with Malaysia’s ratification on Sept. 30, it now has 46.

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