The New START pact has been in place since 2010, imposing crucial limits on nuclear weapons. It's about to end.
In a matter of hours, the final nuclear treaty still in force between the US and Russia is set to expire, and there are grave fears about what comes next.
The New START Treaty, signed in 2010 by then-US president Barack Obama and then-Russian president Dmitry Medvedev, imposed limitations on how many nuclear warheads each country could have deployed.
Observers have warned its abandonment could signal a new era of nuclear proliferation, even as other nations such as China seek to increase their own arsenal of the devastating weapons.
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The treaty was set to expire in 2021, but was extended for five years.
The clock will run out on Thursday, February 5, northern hemisphere time - or some time overnight in Australia.
Russian President Vladimir Putin last year offered to agree to a one-year extension, but US President Donald Trump has so far been non-committal.
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The US, meanwhile, is about to sit down with Iranian representatives in Oman to discuss Tehran's nuclear program.
A White House official speaking anonymously told The Associated Press Trump wanted to keep limits on nuclear weapons globally, and involve China in any talks.
Trump would make a decision on nuclear arms control "on his own timeline," the official said.
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Kremlin adviser Yuri Ushakov said Putin discussed the pact's expiration with Chinese President Xi Jinping, but noted Washington had not responded to his proposed extension.
Russia would "act in a balanced and responsible manner based on thorough analysis of the security situation," Ushakov said.
Arms control advocates have long voiced concerns about the expiration, warning it could lead to a new arms race, foment global instability and increase the risk of nuclear conflict.
https://x.com/Pontifex/status/2019040748298178970Pope Leo XIV called for the treaty "not to be abandoned without seeking to ensure its concrete and effective continuation".
Failure to agree on keeping the pact's limits would likely encourage a bigger deployment, said Daryl Kimball, executive director of the Arms Control Association in Washington.
"We're at the point now where the two sides could, with the expiration of this treaty, for the first time in about 35 years, increase the number of nuclear weapons that are deployed on each side," Kimball told AP.
"And this would open up the possibility of an unconstrained, dangerous three-way arms race, not just between the US and Russia, but also involving China, which is also increasing its smaller but still deadly nuclear arsenal."
The New START agreement limited both nations to 1550 accountable deployed strategic nuclear warheads and bombs, and counted each heavy bomber as one warhead.
That's about 30 per cent below the 2200-warhead limit set by the previous agreement, the 2002 Strategic Offensive Reductions Treaty.
New START also limited Russia and the US to no more than 700 deployed intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and heavy bombers assigned to nuclear missions, apiece.
Deployed and nondeployed ICBM launchers, SLBM launchers and bombers were limited to 800.
"If New START ends, the US and Russia could virtually double their deployed nuclear weapons in about six months," Dr Tillman Ruff, of the International Campaign to Abolish Nuclear Weapons (ICAN) Australia, told 9news.com.au previously.
With Associated Press
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