The head of the Russian space agency said Friday that the Sarmat intercontinental ballistic missile, which Moscow claims can deploy 10 or more nuclear warheads and move at hypersonic speeds to outwit defenses, had been put "on combat duty,” according to state media outlet RIA Novosti.

Pavel Luzin, a Russian military analyst, said the announcement meant that the missile had been deployed in a silo and was ready to be used. That readiness, however, might be more "on paper” than in reality, he added, given the Sarmat’s limited amount of testing.

The space agency director, Yuri Borisov, did not give details of what he meant by "combat duty,” nor did he say how many of the missiles had been deployed or where.

In April 2022, Russia announced that it had successfully launched the Sarmat. At the time, President Vladimir Putin said the missile would show Russia’s adversaries that they needed to "think twice” before threatening his country.

Friday’s announcement appeared to be an attempt to send a further political signal to the West, experts said: a warning that increased Western aid to Ukraine could have dangerous consequences for the world, even if the Sarmat missiles themselves are not destined for the battlefield there.

"The Kremlin is concerned that its nuclear threats do not work anymore and is trying to revive the fear of Russian nuclear weapons in the U.S. and Europe,” Luzin said.

The fear that Russia might use nuclear weapons was once considered a relic of the Cold War, but several factors have revived them as a military and diplomatic issue, noted Dr. Matthew Kroenig, an expert on strategic competition with Russia and China at the Atlantic Council and a political science professor at Georgetown University. Those factors include Russia’s repeated threats to use nuclear weapons since it invaded Ukraine last year, the hostile relations between China and the United States and North Korea’s development of its own missiles.

Washington once faced Moscow alone as a possible nuclear threat. Now, the United States has to develop a policy to deal with three nuclear powers at the same time, Kroenig said.

Russia’s nuclear arsenal, the world’s largest, is its main claim to status as a great power, experts said, and the announcement was intended to underscore that to both foreign and domestic audiences.

In Washington, White House spokesperson John Kirby told reporters he could not confirm the Russian reports that the Sarmat was combat ready.

A U.S. official, who lacked authorization to make a statement on the record but spoke on the condition of anonymity, said the deployment had not elevated U.S. fears of a nuclear escalation and appeared to be low-level posturing.

Thomas Karako, a senior fellow at the Center for Strategic and International Studies in Washington, concurred. "There’s some saber-rattling going on. We’ve seen this train coming for a long time. Russia has been recapitalizing its nuclear arsenal for five or 10 years. We’re now seeing the fruit of that investment.”

Kroenig said the Sarmat represented the culmination of a Russian modernization effort, while U.S. efforts to modernize were just getting started. He noted that the U.S. still relied on Minuteman missiles last upgraded in the 1970s. In contrast to Russia’s claims that the Sarmat can carry 10 nuclear warheads, he added, the Minuteman can carry three.

Russia first announced that it was developing the Sarmat in 2018 and originally planned to deploy the missile late last year, but did not meet that goal. Putin said in June that the new weapon would be deployed "soon” and would "force all who are trying to threaten our country in the heat of frenzied, aggressive rhetoric to think twice.”

What sets it apart is Russia’s claim that the Sarmat will be able to evade defense systems the United States is trying to develop, to shoot down incoming intercontinental missiles. The missile would release several "reentry vehicles” each carrying a warhead, high above the earth, to plunge toward its targets. Moscow says that those vehicles can maneuver at extremely high speeds, making them all but impossible to hit.

"Putin certainly has an interest in hyping it,” said Vann Van Diepen, a former weapons analyst in the Office of the Director of National Intelligence.

Developing such a system would mean overcoming serious technical challenges, he said, but if it works as advertised, it "could be a challenge for U.S. missile defense.”

The Sarmat is a replacement for the Voevoda, or SS-18, the biggest and most deadly Soviet-era missile. According to Putin’s description in 2018, the Sarmat’s weight exceeds 200 tons, and it can fly over the North or South poles and strike targets anywhere in the world. Its trajectory would take it into space.

In February, Putin announced that Russia was suspending its participation in the 2010 New Start treaty, which limits both sides to deploying 1,550 nuclear warheads. The Biden administration had agreed to extend the treaty until January 2026, although prospects for a new one appear dim given current relations.

This article originally appeared in The New York Times © 2025 The New York Times Company