In a stunning eight-day reversal, Donald Trump on Friday announced his denuclearization summit with North Korean leader Kim Jong Un will occur on June 12. But the U.S. commander in chief immediately tried to lower expectations for its outcome.

“You people are going to have to travel because you’re going to be in Singapore on June 12,” he told reporters during an impromptu South Lawn gaggle following a historic meeting with one of Kim’s top lieutenants. “I think it’ll be a process. … But the relationships are building, and that’s a positive thing.”

The president often makes bold promises, as he did as a candidate, but he was much more measured on Friday after he posed for pictures with senior North Korean official Kim Young Chul following a nearly 90-minute Oval Office meeting that included delivery of a letter from the North Korean dictator to Trump.

“We’re not going to go in and sign something on June 12. We never were,” he told reporters. “We’re going to start a process. I think they want to see something happen.”

Trump claimed he believes Kim is willing to give up his atomic weapons — but over time, saying: “I think they want to do that. I know they want to do that.”

“But they want other things along the line,” Trump said. “They want to develop as a country.”

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That would mean the removal or relief of many U.S. and international sanctions. But getting agreement on that will require agreement on just what the term “denuclearize” means. So far, the two sides have much different definitions: The Trump administration says it means Kim gives up all of his atomic arsenal, but North Korean officials have indicated that is unlikely.

“He’d like to see something happen,” the U.S. president said of Kim. “He’s going to be careful. He’s not going to run and do something.”

The North Korean officials he met with Friday did bring up existing U.S. sanctions, but Trump vowed he will not agree to lift any unless there is a solid nuclear pact down the road. But he did sound open to the idea one day.

“I look forward to the day I can take sanctions off North Korea,” he said.

At one point during his back-and-forth with a group of reporters that was on the South Lawn for the entirety of the meeting, the president indicated he had read Kim’s letter.

He said it was “very nice” and “very interesting,” teasing a reporter who asked what it said by jokingly asking that journalist indicate how much he would pay to find out: “Oh, would you like to see what is in that letter. How much? How much?” (Trump later appeared to not have yet read Kim’s letter, saying he did not want to open it in front of the visiting official.)

Trump again floated the carrot of taking steps to make Kim believe he will be protected — and allowed to remain in power — if he does give up his nuclear weapons.

“We’re going to make sure they’re secure, Trump said. “When this is over, it’s over.

The U.S. commander in chief summed up his Oval Office session this way: “Good meeting today. I think it’s a great start.”

‘Tremendous anger’

The president’s announcement that the talks were back on came just eight days after, in a letter senior aides say he dictated “every word” of, told Kim the summit was off due to the North’s “tremendous anger and open hostility” in a statement last week.

Trump’s words Friday and those in a section of the May 24 letter show how the last eight days have been a rollercoaster, with the president and his top aides vacillating by the hour on the status of the denuclearization talks. The president used the letter to send a warning to the North Korean dictator: “You talk about your nuclear capabilities, but ours are so massive and powerful that I pray to God they will never have to be used.”

He did the same during remarks at the start of a bill-signing event at the White House later that day when he announced he said the U.S. military is “ready” and “by far” the most powerful in the world, contending it has been “greatly enhanced.”

Republican and Democratic lawmakers — even those skeptical Trump can reach a meaningful deal with Kim — say it is worth trying to have the one-on-one summit. But Friday’s announcement following delivery of Kim’s letter and the lengthy Oval Office meeting now cast the GOP president against members of his own party on Capitol Hill.

That’s because many hawkish Republicans hailed the president when — just eight days ago — he abruptly canceled the June 12 summit after harsh words by the Kim government for members of his administration.

Trump ally Sen. Tom Cotton of Arkansas, a member of the Armed Services and Intelligence committees, said in a statement last Thursday that “North Korea has a long history of demanding concessions merely to negotiate.”

“While past administrations of both parties have fallen for this ruse, I commend the president for seeing through Kim Jong Un’s fraud,” Cotton said. “As I have long said, our maximum-pressure campaign on North Korea must continue.”

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But agreeing to revive the Kim summit aligns the president with GOP members who responded to his cancellation by urging him to stick with diplomacy and ignore his own hawkish instincts.

“Our goal is to peacefully end North Korea’s nuclear threats,” House Foreign Affairs Chairman Ed Royce of California said in a statement. “The administration should continue to look for opportunities while applying maximum diplomatic and financial pressure against Kim Jong Un.”

‘Art of diplomacy’

Sen. Ben Cardin of Maryland, a senior Foreign Relations member, on Thursday warned Trump’s see-sawing and transactional approach to North Korea and other global matters could backfire.

“With this administration, with the Trump administration, we don’t follow the normal diplomatic path. I think that’s unfortunate,” Cardin said. “ think there’s risk factors. There could be miscalculations. But I am anxious to move forward so that diplomacy has a chance.”

Cardin told CNN that Trump “needs to make it clear that … the United States will not be silent in regards to what they’ve done in the hacking issues, what they’ve done on the human rights front. And that yes, we’re prepared to meet for a diplomatic answer to end the nuclear program on the Korean Peninsula, but it does not mean we’re going to ignore the other issues.”

Other Democrats, including the ranking member of that panel, Robert Menendez of New Jersey, said on May 23 members his party “applaud the robust diplomatic efforts to try to denuclearize the Korean Peninsula.” But he also said he is concerned Trump and his team are not adequately prepared for actual deal-making with Kim.

“The art of diplomacy is a lot harder than the art of the deal,” Menendez said. Democrats have been “deeply concerned that the lack of deep preparation that is necessary before such a summit is even agreed to … was not taking place.”