The top US diplomat tasked with negotiating with North Korea just laid out a denuclearization plan that’s destined to fail.

In his first public comments since President Donald Trump and North Korean leader Kim Jong Un met in Vietnam last month, Stephen Biegun, the US special representative for North Korea, told a Washington audience Monday that the administration wants Pyongyang to give up all of its weapons of mass destruction before anything else.

“We are not going to do denuclearization incrementally,” the envoy said at the Carnegie Endowment for International Peace’s nuclear conference. “The foundation of US policy is denuclearization.”

But it’s not just nuclear weapons: The Trump administration also wants the complete removal of chemical and biological weapons from North Korea, Biegun said, meaning the US wants Pyongyang only to have conventional weapons by the end of the process.

Let’s be extremely clear about what this means: If the US maintains this position, any chance for the US to convince North Korea to part with its nuclear arsenal is gone.

Pyongyang for years has said that the only way it would consider giving up its nuclear weapons is through a step-by-step process where both sides offer reciprocal, commensurate concessions. By resolving smaller disagreements, like lifting sanctions in exchange for the closure of an important nuclear facility, over time the US and North Korea would eventually arrive at the grand prize: the end of Pyongyang’s nuclear program.

But Biegun said the US won’t do that. Instead, the Trump administration wants to see North Korea dismantle its nuclear arsenal before it offers any economic or diplomatic benefits. That’s just not going to work, experts say.

“If we don’t move off this position, we have nowhere to go,” MIT nuclear expert Vipin Narang told me. “There’s no zone of agreement if we insist on everything — I mean everything, complete surrender — up front.”

“It’s a formula for continued deadlock,” said Joshua Pollack, a North Korea expert at the Middlebury Institute of International Studies.

The US has hardened its position on North Korea

At least twice during the negotiations over the past year it seemed that the Trump administration had come to understand that a step-by-step approach had the best chance of success.

In Singapore last June, Trump and Kim agreed to a four-step process: The first two steps were about improving US-North Korea ties, and only after this would the third part — discussing denuclearization — come into play.

And this January, just one month before Trump and Kim met in Vietnam, Biegun gave a speech at Stanford in which he effectively said the administration would adhere to a step-by-step approach.

“From our side, we are prepared to discuss many actions that could help build trust between our two countries and advance further progress in parallel on the Singapore summit objectives of transforming relations, establishing a permanent peace regime on the peninsula, and complete denuclearization,” he said.

But on Monday, he seemed to completely change course.

He explained that the administration never had a step-by-step approach in mind. Instead, he said, all four parts of the process are “linked,” noting that North Korea first has to show it’s serious about ending its nuclear program before it receives economic relief or an improvement in the US-North Korea relationship.

“The United States is prepared to act on all of the commitments laid out in the Singapore statement,” Biegun said, but North Korea has to move quickly. “The faster they move, the faster they get to their brighter future.”

It’s unclear why the US position has changed so starkly. One of the main theories is that National Security Adviser John Bolton, a noted North Korea hardliner, has gained more power in the negotiation process. The Washington Post reported last month that Bolton (and Secretary of State Mike Pompeo) have both expressed skepticism at Biegun’s more gradual approach toward North Korea.

On Sunday, Bolton openly championed a harder stance during an appearance on ABC’s This Week. “The president ... is determined to avoid the mistakes prior presidents have made, and one of those mistakes is falling for the North Korean action-for-action ploy,” Bolton said. “And the reason that that doesn’t work, is that what North Korea needs, and it needs it very much right now, is economic relief.”

“The marginal benefit to North Korea of economic relief is far greater than the marginal benefit to us of partial denuclearization,” he continued. By stating that the US won’t abide by the step-by-step approach, then, Biegun perhaps aims to quell internal criticism.

More likely, though, the US now openly holds an “all or nothing” stance toward North Korea. And if that’s the case, the talks are doomed.