JOINT BASE ANDREWS, Md./WASHINGTON (Reuters) - President Donald Trump welcomed three Americans who had been held prisoner in North Korea back home on Thursday, thanking its leader Kim Jong Un for their release and sounding upbeat about a planned U.S.-North Korea summit.

The former prisoners, freed after U.S. Secretary of State Mike Pompeo traveled to Pyongyang for a second meeting with Kim in less than six weeks, landed at around 2:40 a.m. (0640 GMT) at Joint Base Andrews near Washington.

Trump and his wife, Melania, boarded the plane for about five minutes before the three men stepped out, shaking hands with the president and waving to media and military personnel.

“Frankly, we didn’t think it was going to happen and it did,” Trump said after thanking Kim for releasing the men.

“We’re starting off on a new footing. This is a wonderful thing that he released the folks early.”

Trump said he believed Kim wanted to bring North Korea “into the real world” and had high hopes for their planned meeting, which would be the first between a serving U.S. president and a North Korean leader.

“I think we have a very good chance of doing something very meaningful,” Trump said. “My proudest achievement will be - this is part of it - when we denuclearize that entire peninsula.”

Trump and Kim engaged in a bellicose exchange of rhetoric last year over North Korea’s development of nuclear missiles capable of reaching the United States. Tensions began to ease, coinciding with the North’s participation in the Winter Olympics in South Korea in February.

There has been no sign that Pompeo’s visit has cleared up the central question of whether North Korea will be willing to bargain away weapons its ruling family has long seen as crucial to its survival.

However, the release of the three men marked a dramatic victory for Trump’s embattled White House at a time when his foreign policy is under withering criticism after Tuesday’s U.S. withdrawal from the Iran nuclear deal.

His administration has also been under fire for ethics violations and a chaotic turnover of personnel, as well as a federal investigation of whether the Trump campaign colluded with Russia to sway the 2016 presidential election.

MADE-FOR-TV MOMENT

The arrival of the released prisoners in the dead of night created a made-for-TV moment for Trump, a former reality television host.

“I think you probably broke the all-time-in-history television rating for three o’clock in the morning,” Trump joked to cameras.

Details of the planned Trump-Kim summit have yet to be announced, but a U.S. official, speaking on condition of anonymity, said Singapore had emerged as the likeliest location.

Trump said it would be held in a few weeks and details would be announced within three days.

The three former prisoners were Korean-American missionary Kim Dong-chul, detained in 2015 and sentenced in 2016 to 10 years’ hard labor; Kim Sang-duk, also known as Tony Kim, who taught for a month at the foreign-funded Pyongyang University of Science and Technology (PUST) before he was arrested in 2017; and Kim Hak-song, who also taught at PUST and was detained last year.

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They appeared to be in good health but were taken to Walter Reed National Military Medical Center in nearby Maryland for further medical evaluation.

“I was treated in many different ways, but overall I had to do much labor and when I became ill I received some treatment,” Kim Dong-chul said via a translator.

The trio thanked Trump and other officials for bringing them home. “We thank God, and all our families and friends who prayed for us and for our return,” they said in a statement released as their plane made a stop in Alaska.

Until now, the only American released by North Korea during Trump’s presidency was Otto Warmbier, a 22-year-old university student who returned home in a coma last summer after 17 months in prison and died days later. His death escalated U.S.-North Korea tensions.

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Trump said he wanted to pay his “warmest respects” to Warmbier’s parents.

North Korean state media said the three were arrested either for subversion or “hostile acts” against the government. A North Korean official told Pompeo that Kim had granted the three “amnesty,” a senior U.S. official said.

‘NO CLARITY’

The release appeared to signal an effort by Kim to improve the mood for the summit and followed a recent pledge to suspend missile tests and shut a nuclear bomb test site.

Trump has credited his “maximum pressure” campaign for drawing North Korea to the table and vowed to keep sanctions in place until Pyongyang takes concrete steps to denuclearize.

But former spy chief Kim Yong Chul, director of North Korea’s United Front Department, said in a toast to Pompeo over lunch in Pyongyang: “We have perfected our nuclear capability. It is our policy to concentrate all efforts into economic progress ... This is not the result of sanctions that have been imposed from outside.”

Bonnie Glaser, an Asia expert at Center for Strategic and International Studies, said that while the release of the detainees was not an explicit precondition for a Trump-Kim meeting, the North Koreans understood that they had to do it for any progress to be made.

“The North Koreans have still said nothing to indicate that they are willing to give up their nuclear weapons” she said.

“We have no clarity about Kim’s intentions.”

Vice President Mike Pence echoed that caution, even while praising Kim for making moves toward peace.

“What Kim Jong Un has said publicly and in discussions is that he is prepared to negotiate to achieve complete denuclearization of the Korean Peninsula,” Pence told the CBS “This Morning” program on Thursday. “Those words are important, but we’ll see what they mean.”

A land divided - tmsnrt.rs/2KdXMcS

American detainees in North Korea - tmsnrt.rs/2pmE3ks