(Adds KCNA, Victor Cha, Chinese media reaction)
* North Korea to get security in exchange for denuclearization
* No details on how denuclearization would be achieved
* Joint Trump-Kim Jong Un statement omits mention of sanctions
* Human rights left out of Trump-Kim joint statement
By Steve Holland, Soyoung Kim and Jack Kim
SINGAPORE, June 12 (Reuters) - U.S. President Donald Trump made a stunning concession to North Korean leader Kim Jong Un on Tuesday about halting military exercises, pulling a surprise at a summit that baffled allies, military officials and lawmakers from his own Republican Party.
At a news conference after the historic meeting with Kim in Singapore, Trump announced he would halt what he called "very provocative" and expensive regular military exercises that the United States stages with South Korea.
That was sure to rattle close allies South Korea and Japan. North Korea has long sought an end to the war games.
Trump and Kim promised in a joint statement to work toward the "denuclearization" of the Korean Peninsula, and the United States promised its Cold War foe security guarantees. But they offered few specifics.
The summit, the first between a sitting U.S. president and a North Korean leader, was in stark contrast to a flurry of North Korean nuclear and missile tests and angry exchanges of insults between Trump and Kim last year that fueled worries about war.
Highlighting the change in tone, North Korea's state-run news agency reported early on Wednesday that Kim and Trump had accepted invitations to visit each other's countries. No dates were disclosed.
Noting past North Korean promises to denuclearize, many analysts cast doubt on how effective Trump had been at obtaining Washington's pre-summit goal of getting North Korea to undertake complete, verifiable and irreversible steps to scrap a nuclear arsenal that is advanced enough to threaten the United States.
Pyongyang's Korean Central News Agency (KCNA) reported that Trump offered to lift economic sanctions on North Korea.
Trump "expressed his intention to halt the U.S.-South Korea joint military exercises, which the DPRK side regards as provocation, over a period of good-will dialogue between the DPRK and the U.S., offer security guarantees to the DPRK and lift sanctions against it along with advance in improving the mutual relationship through dialogue and negotiation," it said.
North Korea's formal name is the Democratic People's Republic of Korea.
While suggesting Pyongyang would take mutual goodwill measures, KCNA made no mention of abandoning the country's nuclear program.
Critics in the United States said Trump had given away too much at a meeting that provided international standing to Kim. The North Korean leader had been isolated, his country accused by rights groups of widespread human rights abuses and under U.N. sanctions for its nuclear and ballistic missile programs.
If implemented, the halting of the joint military exercises would be one of the most controversial moves to come from the summit. The drills help keep U.S. forces at a state of readiness in one of the world's most tense flashpoints.
"We will be stopping the war games which will save us a tremendous amount of money, unless and until we see the future negotiation is not going along like it should. But we'll be saving a tremendous amount of money, plus I think it's very provocative," Trump said.
His announcement was a surprise even to President Moon Jae-in's government in Seoul, which worked in recent months to help bring about the Trump-Kim summit.
The presidential Blue House said it needed "to find out the precise meaning or intentions" of Trump's statement, while adding it was willing to "explore various measures to help the talks move forward more smoothly."
There was some confusion over precisely what military cooperation with South Korea that Trump had promised to halt.
U.S. Senator Cory Gardner told reporters that Vice President Mike Pence promised in a briefing for Republican senators that the Trump administration would "clarify what the president talked about" regarding joint military exercises.
"VP was very clear: regular readiness training and training exchanges will continue ... war games will not," Gardner later wrote on Twitter.
Pentagon officials were not immediately able to provide any details about Trump’s remarks about suspending drills, a step the U.S. military has long resisted.
One South Korean official said he initially thought Trump had misspoken.
"I was shocked when he called the exercises 'provocative,' a very unlikely word to be used by a U.S. president," the official said, speaking on condition of anonymity.
Current and former U.S. defense officials expressed concern at the possibility the United States would unilaterally halt military exercises without an explicit concession from North Korea that lowers the threat from Pyongyang.
The U.S.-South Korean exercise calendar hits a high point every year with the Foal Eagle and Max Thunder drills, which both wrapped up last month.
U.S. military drills have been dialed back previously to encourage Pyongyang to cooperate. U.S. President George H.W. Bush agreed to cancel the huge "Team Spirit" joint military drills in 1992 in hopes the North would implement inspections agreements. The drills were eventually phased out.
'DIFFICULT TO DETERMINE'
In a Twitter post as he returned from Singapore, Trump hailed his "truly amazing visit" and insisted that "Great progress was made on the denuclearization of North Korea."
Later, he tweeted: "There is no limit to what NoKo can achieve when it gives up its nuclear weapons and embraces commerce & engagement w/ the world."
Republican Senator Lindsey Graham, who said Trump called him from Air Force One, praised the president's leadership at the summit.
"The President has given Kim Jong Un a way out that is good for him and the world. I hope Kim is smart enough to take it. Well done, Mr. President," Graham said on Twitter.
But concerns persisted about the vague nature of the public agreements.
The Republican chairman of the U.S. Senate Foreign Relations Committee, Bob Corker, said in a statement: "While I am glad the president and Kim Jong Un were able to meet, it is difficult to determine what of concrete nature has occurred."
World stock markets were little changed on Tuesday, while the U.S. dollar rose slightly against an index of major currencies, as investors brushed aside the summit.
The two leaders smiled and shook hands at their meeting at the Capella hotel on Singapore's resort island of Sentosa, and Trump spoke in warm terms of Kim at his news conference.
Just a few months ago, Kim was an international pariah accused of ordering the killing of his uncle, a half-brother and hundreds of officials suspected of disloyalty. Tens of thousands of North Koreans are imprisoned in labor camps.
The leaders' joint statement did not refer to human rights. Trump said he had raised the issue with Kim, and he believed the North Korean leader wanted to "do the right thing."
Trump said he expected the denuclearization process to start "very, very quickly" and it would be verified by "having a lot of people in North Korea.".
He said Kim had announced that North Korea was destroying a major missile engine-testing site, but sanctions on North Korea would stay in place for now.
It was unclear if negotiations would lead to denuclearization, or end with broken promises, as happened in the past, said Anthony Ruggiero, senior fellow at Washington's Foundation for Defense of Democracies think tank.
But Victor Cha, who handled North Korea policy under former President George W. Bush, praised Trump's unorthodox diplomacy and willingness to engage Kim directly.
"Despite its many flaws, the Singapore summit represents the start of a diplomatic process that takes us away from the brink of war," Cha wrote in the New York Times.
DENUCLEARIZATION
The leaders' joint statement said Trump "committed to provide security guarantees" to North Korea and Kim "reaffirmed his firm and unwavering commitment to complete denuclearization of the Korean Peninsula".
North Korea has long rejected unilateral nuclear disarmament, instead referring to the denuclearization of the peninsula. That has always been interpreted as a call for the United States to remove its "nuclear umbrella" protecting South Korea and Japan.
The joint statement made no mention of the sanctions on North Korea and there was no reference to formally ending the 1950-53 Korean War, which killed millions of people and ended in a truce.
But it said the two sides had agreed to recover the remains of prisoners of war and soldiers missing in action, so they could be repatriated. The Pentagon said on Tuesday that nearly 7,700 U.S. military personnel are unaccounted for from the Korean War.
Trump said China, North Korea's main ally, would welcome the progress he and Kim had made.
The Singapore summit did not get top billing in Chinese newspapers on Wednesday. The ruling Communist Party's main newspaper, the People's Daily, reported the news in a brief page 3 article about the Chinese Foreign Ministry's reaction to the talks.
The English-language China Daily said in an editorial that while it remained to be seen if the talks would be a defining moment in history, the fact that the talks went smoothly was a "positive result".
"While no one should expect the summit to have ironed out all the differences and erased the deep-seated mistrust between the two long-time foes, it has ignited hopes that they will be finally able to put an end to their hostility and that the long-standing peninsula issues can finally be resolved. These hopes should not be extinguished," it said.
(Reporting by Steve Holland, Soyoung Kim and Jack Kim; Additional reporting by Dewey Sim, Aradhana Aravindan, Himani Sarkar, Miral Fahmy, John Geddie, Joyce Lee, Grace Lee, Matt Spetalnick and David Brunnstrom in Singapore, Christine Kim in Seoul, John Ruwitch in Beijing and Phil Stewart, Doina Chiacu, Patricia Zengerle, Richard Cowan and Idrees Ali in Washington; Writing by Alistair Bell and Warren Strobel; Editing by Frances Kerry, Peter Cooney, Grant McCool)
