NEW YORK — Russian President Vladimir Putin’s warnings that he would consider using nuclear weapons is a “repugnant threat” that shows the urgency of moving to eliminate nuclear weapons from arsenals around the world, said Cardinal Pietro Parolin, Vatican secretary of state.

Putin’s threat “illustrates just how close the world has come to the abyss of nuclear war. This looming threat, with devastating implications for all humanity, demonstrates that ‘nuclear weapons are a costly and dangerous liability,’ which undermines international security,” the cardinal said Sept. 26 at the U.N. high-level meeting to commemorate the International Day for the Total Elimination of Nuclear Weapons.

In a speech Sept. 21, Putin said, “I want to remind you that our country also has various means of destruction … and when the territorial integrity of our country is threatened, to protect Russia and our people, we will certainly use all the means at our disposal.”

“It’s not a bluff,” he said during his televised address, according to the Associated Press.

Noting Pope Francis’ insistence that “the ultimate goal of the total elimination of nuclear weapons becomes both a challenge and a moral and humanitarian imperative,” Cardinal Parolin told his U.N. audience that nations possessing nuclear weapons seem to be “increasing their reliance on nuclear deterrence” rather than moving toward disarmament.

And, on an international stage, the cardinal said, little progress is being made to encourage more countries to sign commitments under the terms of the Nuclear Non-Proliferation Treaty.

“Achieving the total elimination of nuclear weapons requires a response that is ‘collective and concerted, based on mutual trust’ and considers the catastrophic humanitarian and environmental consequences of nuclear use,” the cardinal said, quoting Pope Francis.

“As long as nuclear weapons exist,” he added, “we cannot rule out the possibility of their use, which threatens ‘any possible future for our common home’ as well as humankind’s very existence.”

Longtime diplomat Rose Gottemoeller, who is Catholic and served with NATO from 2016 to 2019, told Catholic News Service Sept. 22 that action to deter Russia’s use of tactical nuclear weapons is necessary to prevent thousands of deaths and widespread radiation contamination.

The decision to use a nuclear weapon in Ukraine would require Putin to assume such a large moral burden for the Russian federation that it could act as a deterrent itself, suggested Gottemoeller, a lecturer at the Center for International Security and Cooperation at Stanford University.

“He could be, at the end of the day, ruining his own farmland. He could be damaging infrastructure that would be so contaminated by radiation that it couldn’t be used. He could be causing damage in terms of health effects on humans,” said Gottemoeller, who was the lead U.S. negotiator of the 2010 New START, the last remaining nuclear arms control agreement between the U.S. and Russia.

Complicating the situation, voting was underway Sept. 23 in four Ukraine regions occupied by Russian troops on whether the areas would declare independence and then join Russia. The polling was hastily arranged and was to continue through Sept. 27.

Political analysts expect the announced outcome to show a majority of residents being in favor of annexation to Russia, which could lead Putin to determine that any attack in those regions would be considered an attack on Russia’s sovereignty and that a nuclear response might follow.

U.S. and Russian diplomats verbally sparred during a U.N. Security Council meeting Sept. 22 called by France to address the war in Ukraine.

U.S. Secretary of State Antony Blinken urged other nations to tell Russia to end its “reckless nuclear threats” immediately.

He also called Russia’s effort to annex Ukrainian territory a “dangerous escalation, as well as a repudiation of diplomacy.”

Action by the Security Council is unlikely because Russia, as a permanent member, has veto power.

The rising tensions have raised concern from Pope Francis, within the U.S. Conference of Catholic Bishops, and among faith-based and secular observers of nuclear weapons policy.

Addressing Rome pilgrims Sept. 21, Pope Francis said the “tragic war” in Ukraine had left “some people thinking of nuclear weapons — that madness,” adding that he had been told about “the savagery, the monstrosities, the tortured corpses” currently found in “tormented Ukraine.”

“The pope has been clear and helpful,” Daryl Kimball, executive director of the Arms Control Association, told CNS, while calling on countries to “say that any and all nuclear threats are illegal, they’re contrary to the charter of the United Nations and they must cease.”

Kimball urged the international community to band together in developing a response in advance of any possible use of a nuclear weapon by Russia.