The U.S. military is developing a ground-launched, intermediate-range cruise missile to counter a similar Russian weapon whose deployment violates an arms-control treaty between Moscow and Washington, U.S. officials said Friday.

The officials acknowledged that the still-under-development American missile would, if deployed, also violate the Intermediate-Range Nuclear Forces Treaty.

The decision is just one of the policy changes laid out in the Nuclear Posture Review ordered up by Donald Trump in one of his first actions as president and released by Pentagon officials on Friday. Another is the intent to develop new low-yield, tactical nuclear weapons.

Many of the changes are meant to counter Russia’s nuclear weapons development. That includes the new ground-launched cruise missile, said Greg Weaver, the Joint Staff’s deputy director of strategic capabilities.

“We need to demonstrate to the Russians that we’re serious about them coming back into compliance with INF and that perhaps they need to be reminded why they signed the INF treaty in the first place,” Weaver told reporters.

The U.S. can develop its missile and remain in compliance with the INF treaty unless the weapon is deployed, he said.

The cruise-missile project — first reported by the Wall Street Journal in November — allows the U.S. to “prepare for a situation that looks different,” Weaver said.

So will the U.S. military deploy the new missile?

“The United States does not violate arms control treaties,” Weaver said. “So we won’t cross the line in violating INF without making a decision to withdraw, but it’s not our intent to withdraw. We have concluded that it’s in our interest to stay in the INF treaty as long as Russia is complying.”

Here’s what the Nuclear Posture Review says about it: “The United States is commencing INF Treaty-compliant research and development by reviewing military concepts and options for conventional, ground-launched, intermediate-range missile systems.”

It’s a move long advocated by foreign-policy hawks like Sen. Tom Cotton, R-Ark., who says developing the missile is necessary to make Russia “suffer consequences for their violations.”

“Solely doing research on a new missile will keep us within the four corners of the treaty—for now—while also signaling to Russia that we won’t abide by their aggression,” he said in a statement when the Pentagon’s plan was first reported in November.

In a series of briefings and interviews in advance of the review’s formal release on Friday, senior defense officials said the document does not call for radical changes to longstanding U.S. nuclear policy and is an appropriate response to provocative actions from Russia, North Korea, China, and Iran. All four are addressed in the report, which spends the most time on Moscow’s nuclear buildup and the U.S. military response. The officials said the changes — including the prospective new missile and low-yield nuclear weapons — will give the U.S. more leverage when negotiating non-proliferation and arms control measure with Russia.

“What we’re trying to do is ensure our diplomats and our negotiators are in a position to be listened to and say, ’We want to go forward on non-proliferation and arms control,’” Defense Secretary James Mattis said Friday morning, hours before the formal release. “At the same time, you do so by having an effective, safe deterrent.”

Weaver said new low-yield nuclear weapons are needed to counter similar Russian weapons.

“We think Russia’s adoption of, and investment in, their coercive escalation strategy indicates that they do not perceive our current posture as sufficient to deny them some significant prospect of success,” he said. “Additional low-yield capabilities...paired with the comprehensive modernization of existing U.S. nuclear forces are designed to address this threat to deterrence.”

Without new U.S. low-yield weapons, defense officials said, Russia might feel emboldened to use tactical nuclear weapons without fear of retaliation since American nuclear response options would be constrained to the far more powerful warheads atop land- and submarine-launched ballistic missiles.

So the review calls for reducing the warhead yield on a small number of already deployed, submarine-launched ballistic missiles and then developing a new sub- or ship-launched cruise missile. These weapons would give the U.S. another way to respond to a Russian use of a low-yield nuclear weapon without having to send American bombers or fighter aircraft into enemy airspace to drop lower-yield air-launched bombs and missiles, these officials say.

“These additional capabilities…will make a U.S. nuclear response to Russian limited use more credible, raising the Russian nuclear threshold, not lowering ours,” Weaver said. “The purpose of these capabilities is to make a U.S. response to nuclear use more credible, not to make U.S. first use more likely. They do not lower our threshold for the initiation of nuclear weapons use in a conflict.”

Arms control advocates disagree, as do 16 Democratic senators who sent Trump a letter urging him to reconsider the NPR’s stance on low-yield weapons.

“I think the Trump Nuclear Posture Review proceeds from the erroneous assumption that there are gaps in the U.S. nuclear deterrent vis a vis Russia,” said Kingston Reif, director for disarmament and threat reduction policy at the Arms Control Association. “Proposing to counter Russia with more usable nuclear weapons is unnecessary, ineffective, and self-defeating.”

Reif argues the U.S. already has “hundreds of nuclear warheads that can be detonated at low yields. New low-yield weapons are a solution in search of a problem.”

Robert Soofer, deputy assistant secretary for nuclear and missile defense policy, in an interview with Defense One — and a separate briefing with reporters in advance of Friday’s release — argued the review did not present radical changes, but instead largely continues longstanding nuclear policies embraced by Democratic and Republican administrations alike.

“I think there’s a lot more continuity and I think that this document represents the traditional approach that we’ve had to nuclear policy, which is a combination of nuclear deterrence and reducing dangers through arms control and nonproliferation,” Soofer said.

Trump’s Nuclear Posture Review pushes for “deterrence and assurance,” he said. “Those have gone to the top of the policy agenda.”

Soofer said that the global security environment has shifted since 2010, when then-President Obama ordered up the last such review, particularly Russia’s modernization of tactical nuclear weapons and simulating their use in exercises. He also noted that the Obama administration had blessed a full modernization of the nuclear triad, and had launched the development of a new stealth bomber, a new ballistic-missile submarine, and new land-based ICBMs.

Soofer argued the Trump administration is not expanding the role of nuclear weapons, but is merely using different language to describe how they would used to deter a “non-nuclear strategic attack.”

“We’re not planning to reduce the role of nuclear weapons,” Soofer said. “By the same token, we’re not planning to increase the role for nuclear weapons.”

A leaked draft of the review suggested that nuclear weapons might be used to respond to a cyber attack, a policy option Soofer said was not included the final version.

Like Weaver, the review says the United States will keep its commitments to nuclear arms treaties. It does not recommend ratifying the Comprehensive Nuclear Test-Ban Treaty, but Soofer said the U.S. will maintain a “nuclear test moratorium.”

“Were Russia agree to agree to return to verifiable arms control measures, to redress the imbalance in non-strategic nuclear forces, the U.S. might agree to limit or forgo acquiring a nuclear [surface-launched cruise missile],” Weaver said.

He said the new tactical nuclear weapons will not lead to an arms race.

“Reducing Russian confidence in their strategy doesn’t require NATO or the United States to match Russian non-strategic nuclear capabilities in either quantity or diversity,” Weaver said.

The review does include nods to efforts to curb non-proliferation and discuss future arms-control agreements.

“We remain receptive to future arms control negotiations if conditions permit,” Soofer said. “Of course you need to have a willing partner to talk and it would be nice if that partner was in compliance with their existing arms control [commitments]. If there’s an opportunity, we will engage.”

Asked how he thought the Russians would respond to the review, Soofer said, “I’m sure they won’t respond well.”

“The only way to get their attention, the only way to get them to come back to the negotiating table, is to start deploying these capabilities,” he said.

Caroline Houck contributed with reporting to this article.