U.S. President Donald Trump and North Korean leader Kim Jong-un concluded a historic summit in Singapore on Tuesday with an unscheduled signing of a document committing their countries to building “a lasting and stable peace regime on the Korean peninsula.”

Pyongyang pledged to work “toward complete denuclearization of the Korean peninsula,” while Washington would “provide security guarantees,” the document said. The U.S. and North Korea would also work together toward “recovering POW/MIA remains.”

However, the communique lacked specifics or concrete measures showing how the goals would be achieved. Analysts noted that many of the pledges had been made by both countries in the past and that the rhetoric was similar to previous declarations.

“It’s very comprehensive. It’s going to happen,” Trump told reporters afterward, saying he was sure Kim would follow through. But he added later: “I may be wrong. I may stand before you in six months and say, ‘Hey, I was wrong.’ I don’t know that I’ll ever admit that, but I’ll find some kind of an excuse.”

Only a few months ago, Pyongyang called Trump a “dotard,” while Trump ridiculed Kim as “Little Rocket Man,” threatened to destroy his country, and declared that “no regime has oppressed its own citizens more totally or brutally than the cruel dictatorship in North Korea.”

On Tuesday, Trump said it was “a great honor” to meet Kim, who is known for having his opponents murdered, including members of his own family, and starving his people. “He is very talented. Anybody that takes over a situation like he did at 26 years of age and is able to run it, and run it tough – I don’t say he was nice,” Trump said, adding: “It’s a rough situation over there….It’s rough in a lot of places, by the way.”

Trump said his talks with Kim were “honest, direct, and productive….We’re prepared to start a new history, and we’re ready to write a new chapter between our nations.”

In a concession to Pyongyang, Trump said the U.S. military would halt its “provocative” exercises around the Korean peninsula. “We will be stopping the war games…unless and until we see the future negotiation is not going along like it should,” he said. “But we’ll be saving a tremendous amount of money. Plus, I think it’s very provocative.”

The unscripted nature of the document signing, and the early confusion about its contents was clearly demonstrated by a tweet from the State Department which simply stated that the two leaders signed “a document.”

Trump, in a post-lunch walk with Kim around the grounds of the Capella Hotel, told reporters they were “heading for a signing.” He also added that talks had gone “better than anybody could have expected.”

Trump and the North Korean leader looked relaxed after the working lunch, with the president showing his armored limousine, nicknamed “The Beast,” to Kim at the end of their walk together.

Prior to the summit, Trump had stressed the importance of first impressions at the meeting. “I think I’ll know very quickly whether or not something good is going to happen. I also think I’ll know whether it will happen fast,” he said at the G-7 summit in Toronto.

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