Russia-US nuclear pact set to end in 2026 and we won’t see another

In February 2026, for the first time in decades, there will be no existing treaty limiting the size of the nuclear arsenals of the United States and Russia. Experts are divided on whether New START has truly made the world safer, but there is much greater agreement on one thing: replacement is unlikely.

The US and Russia first agreed to place limits on their nuclear weapons and allow each to inspect each other's stockpiles under the New START treaty in 1991, which was replaced by New START in 2011. In 2021, Joe Biden and Vladimir Putin agreed to extend the agreement for five years. It expires on February 5 and negotiations over a replacement have stalled.

Tensions were already rising between Russia and the United States when the former staged a full-scale war. invasion of Ukraine in 2022. Just a few months later Russia suspended from weapons inspectionswhich prompted the US to reciprocate. Now in both countries there are discussions about resumption of nuclear testing – militant theater without a practical goal. Replacing the New START treaty now seems more unlikely than ever.

Mark Bell The University of Minnesota says the new treaty, which limits US weapons to the same number as Russia, is unlikely to please the US, which fears it needs enough weapons to contain both Russia and China at the same time. China has 600 nuclear warheadsThat's far fewer than the more than 5,000 the U.S. and Russia have, but it is rapidly expanding its arsenal. Meanwhile, Russia is unlikely to accept a restriction consistent with this argument and aimed at allowing it to have fewer bombs than the United States. And China will not want to be drawn into a new agreement if it limits the number of bombs at current levels, which would interfere with eventual parity with Russia and the United States. Treaties are never easy, but it's a difficult starting point, says Bell.

START I and the New START Treaty were generally perceived as successful. They are, of course, not ideal, but they have a pragmatic and stabilizing influence. But Bell is skeptical about whether they have actually done much to make the world a safer place. “Did they save both superpowers some money? Perhaps. Did they provide a forum that would be useful for cooperation? Yes. But did they fundamentally change the likelihood of war? I don't think so,” he says.

With or without a treaty, there will always be a real risk of nuclear war, Bell says. In many ways, the threat of mutually assured destruction is the best insurance we have now that the atom is split, and it is the unthinkable results of nuclear conflict, not treaties, that actually prevent wars, he says. “The stabilizing effect comes from danger, and it is impossible to get rid of it. This is a feature, not a bug, of nuclear deterrence,” he says.

But some with inside information are more concerned about the contract ending. Stephen Herzog is a fellow at the Middlebury Institute of International Studies in Monterey, California, but previously worked on arms control issues at the US Department of Energy. He said New scientist It can be said unequivocally that the loss of the New START treaty makes nuclear war more likely.

“It makes the world a less safe place because of the lack of transparency, because it allows for unfettered competition from leaders who seem to want to rely on nuclear weapons,” Herzog says. “In a situation where Russia is becoming increasingly unpredictable, and in a situation where the United States administration is unfortunately becoming more unpredictable, the lack of vital confidence-building and transparency-building measures that essentially curb the arms race really frightens me.”

There are several other treaties relating to nuclear weapons. The ambitious Treaty on the Prohibition of Nuclear Weapons aims to completely eradicate them and attracts signatories, but notably non-nuclear powers. Several nuclear-weapon states have signed the Nuclear Non-Proliferation Treaty, but this does little to limit the number of bombs in existence. Only New START truly held the nuclear superpowers accountable.

Herzog believes that if Donald Trump and Putin wanted to, they could immediately agree to a similar deal. Indeed, there were Putin’s proposals, which were warmly received by Trump, that unofficial extension for a year it would be possible to come to an agreement. But there were no negotiations, and such a deal would have been, at best, a short-term solution to the problem.

Philip Blick The Middlebury Institute of International Studies says a continuation could be beneficial if the extra time were used to negotiate a new treaty, but the prospects for long-term arms control are dim. “A one-year extension could make the Russians feel like they have put everything aside and could make them less likely to become involved in the conflict. [in future talks]”, says Blick.

Negotiating a treaty is a complex battle involving politicians, military and spy agencies, with the potential to hide tiny but potentially vital strategic advantages in the fine print, Herzog says. Many key personnel – weapons inspectors, negotiators and nuclear experts – have been fired, laid off or forced to resign by the Trump administration, which could give Russia an advantage, he said.

“If we were to go head-to-head and try to negotiate a new contract, I think there are certain things that we probably wouldn't have enough staff to do,” Herzog says.