U.S. President Donald Trump welcomed home three Americans who had been detained by North Korea, greeting the trio at an air base outside Washington early Thursday after they were released hours earlier by Pyongyang. The release gives Trump a key diplomatic victory ahead of a highly anticipated summit with the North’s leader, Kim Jong Un.

A plane carrying the three former detainees, Kim Hak-song, Kim Dong-chul and Tony Kim, who is also known as Kim Sang-duk, arrived at Andrews Air Force Base in Maryland in the early morning hours Thursday. Trump, first lady Melania Trump, Vice President Mike Pence and his wife, Karen, greeted them on the plane.

Exiting the plane, which was situated beneath a giant American flag, the three beaming men shook hands with Trump, before raising their arms in triumph and making peace signs above their heads.

“It’s like a dream. We’re very, very happy,” they said through an interpreter on the tarmac.

Trump made a point of publicly thanking Kim Jong Un for the release, saying the U.S. was “starting off on a new footing,” but noting that the larger goal of ridding the Korean Peninsula of nuclear weapons remained his focus.

“I’m very honored to have helped these three folks,” Trump said. “They’ve been through a lot. The true honor is going to be if we have a victory in getting rid of nuclear weapons.”

In thanking Kim Jong Un for releasing the three, Trump said he believes the young North Korean leader wants to reach an agreement on denuclearizing the Korean peninsula. “I really think he wants to do something and bring that country into the real world. I really believe that,” the president said.

After brief comments on the tarmac, the three detainees were then transported to nearby Walter Reed National Military Medical Center for further evaluation and medical treatment.

The prisoners’ release removed a key obstacle to Trump’s planned talks with Kim and gave the president a win that he can call a show of goodwill ahead of the meeting.

The White House said in a statement earlier that Trump “appreciates” Kim’s move and saw it as a “positive gesture of goodwill.”

Ahead of their return to the U.S., it said the three appeared to be in good condition, with all able to board the plane in Pyongyang without assistance. They later transferred to a separate aircraft with more extensive medical facilities at Yokota Air Base on the outskirts of Tokyo.

A report Thursday by North Korean state media said that Kim had granted the three men an “amnesty” after accepting an “official suggestion” from the U.S. president, conveyed to him by Secretary of State Mike Pompeo, that they be released.

They were the latest in a series of Americans who have been detained by the North in recent years for seemingly minor offenses and typically freed when top U.S. officials or statesmen personally visited to bail them out.

While no family members were present to greet the detainees, a statement from the family of Tony Kim lauded Trump for his role, thanking him for “engaging directly with North Korea.”

Of the three, Kim Dong-chul, who was arrested on suspicion of espionage in 2015, was held the longest, while Kim Hak-song and Tony Kim, who had worked at Pyongyang University of Science and Technology, were detained last year.

In April 2016, the North sentenced Kim Dong-chul to 10 years of hard labor for carrying out what it described as spy activities. Kim Hak-song was held over “anti-state activities” and Tony Kim was accused of committing unspecified criminal acts intended to overthrow the government.

The trio’s release comes after U.S. national Otto Warmbier was freed while in a coma last June. Warmbier, a University of Virginia student when he was arrested, died soon after returning to the United States following more than 17 months in prison.

Speaking to reporters with the detainees, Trump paid his respects to the parents of Warmbier, calling them “spectacular people.” Fred and Cindy Warmbier have filed a wrongful death lawsuit, accusing the North Korean government of torturing and killing their son.

“We are happy for the hostages and their families,” they said in a statement Wednesday. “We miss Otto.”

At least four South Koreans are still held by the North, while the issue of abductions of Japanese nationals by North Korean agents in the 1970s and ’80s remains a sore point for Japan.

Prime Minister Shinzo Abe on Thursday hailed the Americans’ release, calling the North’s move a “positive” step. Speaking with Trump over the phone, Abe was quoted as saying that he had congratulated the U.S. leader on the “big achievement.”

Abe, who was briefed by Trump about Pompeo’s Wednesday visit to Pyongyang, also confirmed with Trump their common goal of North Korea’s “complete, verifiable and irreversible denuclearization,” according to Deputy Chief Cabinet Secretary Yasutoshi Nishimura.

During the 20-minute phone call, Trump underscored Japan’s key role in North Korean issues, calling it a “big player,” Nishimura said.

Noting the Japanese abductees, Abe pledged to “make utmost efforts to resolve the issue” in cooperation with the United States, South Korea and China.

Abe has long called resolving the abduction issue a top priority of his government.

Tokyo officially lists 17 citizens as abduction victims. While five of them were repatriated in 2002, North Korea maintains that eight have died and the other four never entered the country.

Experts said it was unlikely that the move to release the U.S. detainees would translate into any immediate movement on the Japanese abductee issue.

“I don’t think this step says anything specific about hope for the Japanese abductees, unfortunately,” said James Schoff, an East Asia expert with the Carnegie Endowment for International Peace in Washington. “The abductee issue is something that can only be addressed bilaterally between Kim and Abe, in the context of a broader effort at ‘settling their unfortunate past’ and working toward normalization.”

Japan colonized the Korean Peninsula from 1910 until the end of World War II in 1945, and while it established diplomatic ties with South Korea in 1965, it has yet to do so with the North.

Schoff said that if denuclearization and Korean peace talks move forward, something he called “a big ‘if,’ ” then this would open the door to an Abe-Kim summit.

Kim told South Korean President Moon Jae-in during last month’s inter-Korean summit that he is ready to hold talks with Japan at “any time,” comments that were relayed to Abe in a telephone call shortly after.

Schoff, however, said that the prospects of such a summit would not become clear until after the Kim-Trump meeting.

Pompeo was dispatched by Trump on Wednesday to finalize preparations for the landmark U.S.-North Korea summit, which is focused on ridding the North of its nuclear weapons.

Japanese media reports said Thursday that the U.S. is calling for the North to dispose of all data gleaned from the site of its six nuclear tests, as well as its Nyongbyon nuclear facility. The reports said Washington is also asking that thousands of engineers involved in the country’s nuclear program be moved abroad.

Kim has already said he will shutter the Punggye-ri nuclear site this month and invite foreign experts and journalists to witness the closure.

As for the summit venue, Trump said Thursday that it will take place in Singapore on June 12. “We will both try to make it a very special moment for World Peace!” Trump said in a tweeted announcement.

The U.S. leader had earlier thanked Abe and Moon for the role they played in bringing about the summit.

“I think this is something that nobody thought was going to happen for years or more,” Trump said. “And I really believe it’s going to be a great thing for North Korea, a great thing for South Korea and Japan.”

But Trump reserved more explicit praise for Chinese leader Xi Jinping, thanking him and saying he had been “very helpful to us two days ago on something very specific.” It was unclear what Trump was referring to, but Xi and Kim held surprise talks earlier this week in the Chinese city of Dalian, and the summit was likely to have been high on that agenda.

Andrew O’Neil, an expert on North Korea and a professor at Griffith University in Australia, said that the detainees’ release, as well as the upcoming summit, “needs to be seen in the context of Kim’s dual strategy,” which he said consisted of reaching out to the international community in an effort to ease suffocating sanctions and diplomatic pressure and “promoting the internal narrative that the world is now engaging with North Korea — on its terms.”

O’Neil said Pyongyang understood the red-hot anger in the U.S., including on the part of Trump himself, over the death of Warmbier and that Wednesday’s release “would have been authorized with that in mind.”

“The release also helps clear the decks in terms of immediate outstanding issues and Kim will appreciate that it casts him in a favorable light ahead of the summit as well as allowing Pyongyang to claim that it’s shown benevolence, goodwill, etc. just in case Trump pulls the plug on continuing dialogue if a comprehensive denuclearization commitment doesn’t materialize,” O’Neil said.

On Thursday, North Korea made its first official mention of the planned summit, with Kim calling it a “historic” opportunity, state media reported.

Kim, who has conducted a flurry of diplomatic moves in recent weeks, told Pompeo that a summit with Trump “would be a historic meeting” and an “excellent first step” toward the “building of a good future” on the Korean Peninsula, according to the North’s official Korean Central News Agency.

Over the last two months, the North Korean leader has met with Xi twice as well as with Moon for the inter-Korean summit.

During the meeting with Pompeo, the top U.S. diplomat delivered a verbal message from Trump to Kim, for which the North Korean leader “expressed thanks, highly appreciating that the U.S. president has shown deep interest in settling the issue through dialogue.”

The language was a marked shift from just eight months ago, when the leaders of the two countries traded a series of pointed threats and insults. Pictures released by KCNA and published in the Rodong Sinmun, the ruling Workers’ Party daily, showed Kim and Pompeo laughing together while walking and grinning broadly for a posed photograph.

O’Neil called this “quite extraordinary,” considering the North’s harsh rhetoric and frantic pace of nuclear and missile testing just last year.

“The big question is whether it can be sustained,” he said. “More specifically, can the good vibes at the macro level be converted into detailed outcomes on major issues like denuclearization, mutual recognition, post-armistice negotiations.”

Information from Kyodo added.