When President Donald Trump and North Korean leader Kim Jong Un meet in Singapore next month, assuming they can stay on track long enough to make it happen, they will have two very different agendas.

Washington has set the bar for the summit extremely high — complete, verifiable, irreversible denuclearization. Pyongyang, meanwhile, has a pretty tall order of its own: the complete denuclearization of the Korean Peninsula, with the precondition that the "hostile policy" of the U.S. toward their country must first end.

For sure, bridging that gap will be quite a feat. Both leaders might well opt instead for a "shiny object summit," a meeting that is heavier on photo ops and TV-friendly sound bites than on long-term change.

But what if they really go for a deal?

Here are few of the possibilities they might explore:

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HANDING SOME OVER

Reports, albeit speculative and anonymously sourced, keep popping up that Kim may be willing to hand over several of his nuclear weapons as a sign of sincerity.

As far as theatrics go, this would be hard to top.

It would be a tangible, dramatic move that could happen very quickly — factors that would certainly appeal to the reality TV show side of Trump. It could even be big enough to earn him a shot at that Nobel Peace Prize he says everyone is talking about.

Outlandish as it sounds, something like this was what national security adviser John Bolton had in mind when he suggested the Libya model as a good example for North Korea to follow. After Libya unilaterally decided to give up its fledgling nuclear program in 2003, planeloads of documents, equipment and even centrifuges related to the country's nuclear and missile programs were transported by U.S. military aircraft to the Oak Ridge National Laboratory in Tennessee.

But considering the way leader Moammar Gadhafi was deposed and killed several years later, Pyongyang flipped out at Bolton's suggestion, almost dooming the summit itself. Arms control experts have also noted that, unlike Libya, the North is already a nuclear power. So the Libya model really doesn't fit.

There are other problems, too.

North Korea is believed to have several dozen nuclear weapons, so handing over a few — spectacular as that would be — wouldn't really solve anything unless a further agreement was made regarding what to do with the rest. At the same time, for the North, it would be a huge and painful concession.

Nuclear weapons are top secret for a reason. Giving up even one would potentially reveal details of design and technology that the North's military would rather keep to itself.

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CAP AND FREEZE

Kim has already promised to stop launching intercontinental ballistic missiles and conducting nuclear tests. He even made a big show of demolishing tunnels at Punggye-ri, the North's only known underground testing site.

That's a start.

But North Korea has announced similar moratoriums before, only to change its mind later. Nothing Kim has done so far is either irreversible or particularly costly. And the North hasn't said anything about launching shorter-range missiles, a big concern for U.S. ally Japan, which hosts numerous U.S. military bases.

So, short of immediate denuclearization, the logical next step is for Washington to push for a freeze on production not only of the bombs themselves, but also of missiles and the fissile material — the plutonium and highly enriched uranium — that can be used to make more bombs.

It's quite likely that even at the highest levels American officials don't know how big the North's nuclear arsenal is or where all of its bombs are located. They will need to verify that right off the bat, which won't be easy and will involve a lot of cooperation from Kim.

They will also need to work out a way to verify that the North isn't actively making more, another daunting task that will require monitors on the ground and a lot more transparency than Pyongyang is inclined to be comfortable with.

Washington can't reasonably expect all that to happen without giving something in return. So there will have to be more give-and-take, more talking, more exercises in developing mutual trust and probably a lot more problems and potential deal-breaking disputes along the way.

And that's if everything goes well. Which it never has yet.

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PHASING THEM OUT

The end game here is Trump's goal of total denuclearization, but with provisions that give North Korea time to comply.

Nuclear physicist Siegfried Hecker and Robert Carlin, two of the top experts on North Korea's nuclear program and how to negotiate with Pyongyang, teamed up with another researcher, Elliot Serbin, to produce such a plan for the Center for International Security and Cooperation at Stanford University.

Their roadmap, released on Monday, lays out three phases over 10 years.

It starts essentially with cap and freeze in the first year, a rollback phase of 2-5 years and finally, eliminating or setting mutually acceptable limits on what's left.

Along with the steps Kim has already announced, the report suggests North Korea should "frontload" its efforts to demonstrate its commitment. Pyongyang could, for example, quickly disable its plutonium-producing reactor. Washington should seek early access to its nuclear centrifuge facility at Yongbyon and demand the halt of operations at uranium chemical-processing facilities.

Hecker and Carlin have a lot of credibility.

Hecker was director of the Los Alamos National Laboratory from 1986 until 1997, has visited the North seven times and inspected its nuclear facilities firsthand. Carlin has worked as an analyst for both the State Department and CIA and is widely regarded as one of the top North Korea experts in the world.

Ultimately, no matter what detours or bumps lie ahead, they believe a phased approach is the only realistic path forward.

"Insisting on immediate CVID along a 'Libya model' to eliminate everything up front and virtually all at once is tantamount to a North Korean surrender scenario," they wrote in the report, using the acronym for "complete, verifiable, irreversible denuclearization."

"The suggestion of shipping the North's nuclear weapons out of the country is also naive and dangerous," they wrote.

There are no quick fixes, in other words.

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Talmadge is the AP's Pyongyang bureau chief. Follow him on Instagram and Twitter: @EricTalmadge