(Bloomberg) -- President Donald Trump’s summit with North Korean leader Kim Jong Un produced a historic handshake but all of the work to make the deal a reality lies ahead, with no benchmarks for progress, follow-up meetings scheduled or even common agreement on what success would look like.

The lack of any details contributed to an air of skepticism in Washington about what Trump accomplished, and not just from Democrats. While the president won general praise for talking to Kim -- instead of tweeting at him -- even some Republicans were grasping for concrete takeaways and sounding cautious.

“It’s important that we don’t lose sight of the fact that Kim Jong Un is a butcher and he is a butcher of his own people,” Louisiana Senator John Kennedy, a Republican, said Tuesday. “Trying to reason with someone like that is like trying to hand feed a shark. Doesn’t mean you can’t do it, but you’ve got to do it very, very carefully.”

Confusion flared while Trump was still in the air on the way home from Singapore. The details were so unclear that a Republican senator tweeted out what appeared to be a misunderstanding that the Trump administration was walking back a pledge to end biannual military exercises with South Korea after Vice President Mike Pence gave a closed briefing to lawmakers. The senator later posted a correction.

Canceling the “war games,” as Trump calls them, isn’t even mentioned in the page-and-a-half declaration the two leaders signed, adding to the anxiety about what Trump actually agreed to do.

Leverage at Risk

At the same time, the president risks losing leverage. A Chinese official already signaled the country may ask the United Nations to lift or adjust economic sanctions on North Korea, the basis for the “maximum pressure” campaign Trump has used to push Kim toward disarmament. China, as North Korea’s neighbor and most important trading partner, also could provide relief to Kim by throttling down sanctions enforcement on its own.

Korea analysts and members of Congress see a long road ahead -- and signs in Trump’s celebratory post-summit media blitz that he doesn’t appreciate the challenges.

“There’s really a very, very far way to go because this initial step was so small and disappointing,” said Bruce Klingner, a former deputy division chief for Korea at the Central Intelligence Agency and senior research fellow for Northeast Asia at the conservative Heritage Foundation.

When Trump Met Kim: In Pictures

The next developments may come when Secretary of State Mike Pompeo visits Seoul on Wednesday for meetings with his South Korean and Japanese counterparts before heading to Beijing for a few hours to talk with Chinese leaders. Trump said he, Pompeo, National Security Adviser John Bolton and other U.S. officials will meet again next week.

‘Earliest Possible’ Meeting

The document signed Tuesday by Trump and Kim specifies that Pompeo and a “relevant high-level” North Korean official will meet “at the earliest possible date.” Trump also promised he would have “many meetings” with Kim in the future.

Trump sees a win in just getting Kim to the negotiating table, even though it was Kim who first proposed the talks. And the president believes the two established the kind of personal relationship that will help cement a deal.

“He trusts me, I believe, I really do,” Trump said of Kim in an ABC News interview. “I think he trusts me, and I trust him.”

The president enthused in a series of tweets from Air Force One as he flew back over the Pacific Ocean that the meeting in Singapore was “truly amazing” and he “Got along great with Kim Jong-un who wants to see wonderful things for his country.”

Trump described the next steps only vaguely and offered no specifics on how his administration will verify Kim’s actions. “We’re going to be following things. We’re going to be monitoring things. We’re dealing with him ... on a constant basis,” Trump said in the ABC News interview.

‘There’s Momentum’

Follow-ups should begin “immediately,” said Bill Richardson, President Bill Clinton’s ambassador to the United Nations, who visited North Korea several times to negotiate for the release of detained Americans. Technical working groups should re-engage next week because “there’s momentum -- you don’t want to lose momentum in politics.”

Trump has gotten his photo op and may want to step back and leave the nuts and bolts to his team, but that could be damaging to the process, Richardson said Tuesday on Bloomberg Television. “If you wait and if the president disengages and says ‘I’m moving on to my next issue,’ that’s not good.”

Kim got much of what he wanted out of the U.S. with just his first meeting with Trump: The appearance of legitimacy on the world stage, a verbal agreement by Trump to end joint U.S.-South Korean military exercises, a security guarantee and no pressure on human rights.

Trump was already suggesting Tuesday that some leeway is possible on the economic sanctions at the core of his strategy on North Korea.

The sanctions will stay in place for the time being but could be eased even before the “complete denuclearization” of the Korean Peninsula -- however that’s ultimately defined by both sides -- is verified, he indicated. “I hope it’s going to be soon,” Trump said at his press conference. “At a certain point, I actually look forward to taking them off.”

‘Political Flexibility’

The sanctions “need to stay in place until North Korea verifiably and irreversibly dismantles its nuclear arsenal,” said Andrea Berger of the Middlebury Institute of International Studies at Monterey. “But there’s a certain amount of political flexibility in sanctions relief in an era where Trump is at the helm.”

Another lever of U.S. pressure on North Korea has been its military war games with South Korea, which have placed a security threat right at Kim’s southern border. Trump agreed to end biannual exercises, though regular readiness training on the peninsula will continue, Pence told Republican lawmakers Tuesday in the briefing that led to some confusion.

Keeping North Korea engaged in negotiations may prove difficult given Trump’s apparent concessions on military exercises, according to Robert Manning, a senior fellow with the Scowcroft Center for Strategy and Security at the Atlantic Council.

“We shouldn’t be talking about peace treaties and troop reductions that get ahead of force reductions and dismantling of nuclear weapons and ballistic missiles,” Manning said. “I’m puzzled by why we’re giving specifics about what we’re going to do, and we have no sense of any progression or even definition of how we’re going to get nuclear weapons dismantled, disabled and destroyed.”

‘History of Deceit’

Even fellow Republicans are concerned that Trump is being too credulous of the North Korean leader.

“We must always be clear that we are dealing with a brutal regime with a long history of deceit,” House Speaker Paul Ryan cautioned. “Only time will tell if North Korea is serious this time, and in the meantime we must continue to apply maximum economic pressure.”

“The next steps in negotiation will test whether we can get to a verifiable deal which enhances the security of Northeast Asia, our allies, and of course the United States,” Senate Majority Leader Mitch McConnell said.

Trump’s praise for Kim, who told reporters that the dictator “loves his people,” triggered concern, especially among Democrats, that the president might not pressure Kim to improve the treatment of those people.

“Kim was lavished with praise by President Trump as if he was a prospective investor in a Trump real estate development on North Korea’s ‘great beaches,’ not one of the world’s worst human rights violators who was responsible for the death of American citizen Otto Warmbier,” said California Representative Adam Schiff, the top Democrat on the House Intelligence Committee.

--With assistance from Daniel Flatley.

To contact the reporter on this story: Jennifer Epstein in Washington at jepstein32@bloomberg.net

To contact the editors responsible for this story: Alex Wayne at awayne3@bloomberg.net, Mike Dorning, Larry Liebert

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