The Trump administration’s ongoing review of U.S. nuclear strategy could call for two new submarine-launched atomic weapons. One of the new weapons, a less-destructive version of the Navy’s Trident ballistic missile, appears to be part of a risky plan for lowering the threshold for nuclear retaliation.

Experts say a lower threshold raises the likelihood of atomic apocalypse. “The new policies only increase the chances of blundering into a nuclear war,” Bruce Blair, a Princeton University nuclear scholar, told The Daily Beast.

Trump’s Nuclear Posture Review, which will succeed Obama’s 2010 nuclear review, is slated for public release in coming weeks. Some experts and policymakers have seen drafts of the review, one of whom shared details with The Daily Beast on condition of anonymity.

According to the source, the new review will direct the U.S. nuclear-weapons establishment—which includes the Defense Department and the Department of Energy—to develop a nuclear-tipped cruise missile for the Navy’s guided-missile and attack submarines, plus a new version of the Trident intercontinental ballistic missile that equips the fleet’s ballistic-missile submarines.

It’s unclear how fast Trump will want the new weapons. Designing, testing, and building a new atomic munition design can take decades and cost tens of billions of dollars.

The Pentagon’s current nuclear-modernization effort, which began under Obama and includes new bombers and submarines but no brand-new missiles or warheads, is projected to cost up to a trillion dollars over 30 years. The Pentagon completed its last totally new atomic warhead design in the early 1980s.

It’s also unclear how many new missiles the administration aims to acquire. The United States possesses around 4,000 atomic warheads, but the New START treaty with Russia limits the number of ready-to-use warheads to just 1,550. The same treaty caps the number of nuclear “delivery vehicles”—missiles, bombers, and submarines—to just 700.

If the Pentagon gets new nukes, it might have to replace some existing weapons—assuming the administration intends to abide by the New START treaty. In October, Trump reportedly said the United States should build up its atomic arsenal to peak Cold War levels, meaning as many as 32,000 warheads.

A build-up of that magnitude “would violate major international treaties,” Geoffrey Wilson, a nuclear expert with Ploughshares Fund, a peace-advocacy group in San Francisco, told The Daily Beast. Not to mention, it would cost roughly “eleventy bazillion dollars,” according to Jeffrey Lewis, director of the East Asia Nonproliferation Program at the Middlebury Institute of International Studies in California.

It’s not safe to assume that Trump and his advisers intend to honor all existing treaties. Indeed, the administration appears to want a new submarine-launched cruise missile because it violates a treaty. Granted, it’s a treaty that Russia violated first.

In 1987, President Ronald Reagan and Soviet Premier Mikhail Gorbachev negotiated the Intermediate Nuclear Forces treaty, which compelled both countries to remove fast-striking medium-range nuclear missiles from their arsenals. The treaty has been credited with helping to ease Cold War tensions.

But sometime before 2014, Russia began developing a new nuclear cruise missile in defiance of the INF treaty. The Obama administration applied diplomatic pressure in the hope of compelling the Kremlin to cancel the new missile. Ignoring American entreaties, Russia reportedly deployed the cruise missile to Eastern Europe in early 2017.

The Trump administration seems to believe a new submarine-launched cruise missile—scores of which could fit aboard the Navy’s four Ohio-class guided-missile submarines—could “pressure Russia into coming back into compliance” with the INF treaty, Blair said.

This planned negotiation-by-nuke is consistent with the Trump administration’s aggressive rhetoric regarding atomic weaponry and planned looser rules for their use. The administration’s national security strategy, released in December, calls nuclear weapons “the foundation of our strategy to preserve peace and stability by deterring aggression against the United States, our allies and our partners.”

In September, Trump notoriously threatened to “totally destroy” North Korea in retaliation for that country’s own nuclear developments.

Ironically, the other new nuclear weapon the administration wants would be designed to be less powerful than most existing U.S. atomic munitions are. But that, too, is part of a risky new strategy.

In addition to a new cruise missile, Trump’s nuclear review calls for a lower-yield version of the Navy’s Trident ballistic missile. Current Tridents include multiple independent re-entry vehicles, or MIRVs, each of which carries its own atomic warhead with an explosive yield of between 100 and 400 kilotons.

Trident’s warheads could be redesigned for lower yield—say, a few kilotons or less. One way of reducing a nuke’s explosive power is to eliminate one of the two atomic stages that today’s warheads typically include. “Only the first stage of the weapons would detonate, making it an atomic ‘fission’ bomb instead of a thermonuclear ‘fusion’ bomb,” Blair explained.

A less destructive Trident would, in theory, give military planners more options for waging “limited” nuclear war. But experts say there’s no such thing as a limited atomic exchange, and less-destructive weapons actually make disaster more likely by fooling leaders into believing they can drop a nuke without world-ending consequences.

“It just takes one nuclear weapon to start Armageddon,” Geoff Wilson and Will Saetren, nuclear scholars with Ploughshares Fund, wrote in a 2016 essay.

Not coincidentally, Trump’s nuclear review also aims broaden the range of threats that the government claims justify atomic retaliation. Where previous administrations reserved nuclear counterattack for extreme cases such as a nuclear sneak-attack, Trump’s review claims that a major hack of U.S. online infrastructure should warrant an atomic response.

In another departure from this “negative security guarantee” policy, Trump’s nuclear review leaves open the possibility of a U.S. nuclear strike on a non-nuclear-armed country. Trump’s review endorses the negative-security policy, but states that the administration reserves the right to reconsider it.