Staging a made-for-TV, still-of-the-night arrival ceremony, U.S. President Donald Trump welcomed home three Americans freed by North Korea and declared their release a sign of promise toward his goal of denuclearizing the Korean Peninsula.

Speaking early Thursday on an air base tarmac with the former detainees by his side, Trump called it a "great honour" to welcome the men to the U.S., but said "the true honour is going to be if we have a victory in getting rid of nuclear weapons."

Trump also thanked North Korea's Kim Jong-un for releasing the Americans and said he believes Kim wants to reach an agreement on denuclearization at their upcoming summit.

"I really think he wants to do something," the president said.

Melania Trump, Vice-President Mike Pence, Secretary of State Mike Pompeo and other top officials joined Trump to celebrate the occasion at Joint Base Andrews near Washington. The men — Kim Dong Chul, Kim Hak Song and Tony Kim — had been released Wednesday amid a warming of relations between the longtime adversaries.

Shortly before 3 a.m. the president and his wife boarded the medical plane on which the men had travelled and spent several minutes meeting with them privately. The group then emerged at the top of the airplane stairway, where the men held up their arms in an exuberant display.

3 men greeted by U.S. president, VP and other dignitaries 1:04

As the men entered into view, U.S. service members on the tarmac burst into applause and cheers.

"This is a special night for these three really great people," Trump told reporters. On the U.S. relationship with North Korea, Trump declared: "We're starting off on a new footing."

The freed prisoners appeared tired but in excellent spirits, flashing peace signs and waving their arms as they emerged from the aircraft. When asked by reporters how it felt to be home, one of the men answered through a translator: "It's like a dream; we are very, very happy." They later gave the president a round of applause.

After Trump's remarks, the three men boarded a bus for Walter Reed National Military Medical Centre, where they were to be evaluated and receive medical treatment before being reunited with their families.

Break from tradition

The White House carefully choreographed the event, hoisting a giant American flag between two fire trucks on the tarmac and inviting reporters to witness the return.

The image-conscious president told reporters: "I think you probably broke the all-time-in-history television rating for 3 o'clock in the morning."

Hours later, Trump tweeted about the event.

On behalf of the American people, WELCOME HOME! <a href="https://t.co/hISaCI95CB">pic.twitter.com/hISaCI95CB</a> —@realDonaldTrump

The highly public and politically tinged display stood in stark contrast to the low-key and very private reception that the State Department had envisioned and carried out from the moment it took custody of the men, in keeping with a tradition of trying to protect potentially traumatized victims from being thrust into the spotlight so soon after their ordeal.

Department officials took great pains on the prisoners' release in North Korea, as well as on their flights to Japan and Alaska, to keep them sequestered not only from the two journalists travelling with Pompeo but also from staffers not immediately involved in their cases. The trio, along with medical personnel that included a psychiatrist, were cloistered in the middle of Pompeo's plane in a small section of 12 business class-size seats that was cordoned off by curtains on both ends.

Donald Trump, left, and Melania Trump greet former North Korean detainees Tony Kim, second from left, Kim Dong Chul, second right, and Kim Hak Song, behind them not seen, upon their arrival. (The Associated Press)

State Department officials refused to discuss anything but the most basic details of their conditions, citing privacy concerns in keeping with the minimal amount of information they had released since the men were imprisoned.

However, in an interview with ABC News, Pence said Pompeo told him that during a refuelling stop in Alaska, "one of the detainees asked to go outside the plane because he hadn't seen daylight in a very long time."

Pompeo had secured their release in Pyongyang after meeting with Kim on final plans for the Trump-Kim summit. The Americans had boarded Pompeo's plane out of North Korea without assistance and then transferred in Japan to a Boeing C-40 outfitted with medical facilities for the trip back to the U.S.

Shortly after they touched down on American soil in Alaska for the refuelling stop on Wednesday afternoon, the State Department released a statement from the freed men.

"We would like to express our deep appreciation to the United States government, President Trump, Secretary Pompeo, and the people of the United States for bringing us home," they said. "We thank God, and all our families and friends who prayed for us and for our return. God Bless America, the greatest nation in the world."

Upcoming summit

Trump announced in a tweet earlier Thursday that the two leaders will meet in Singapore on June 12 as he seeks to negotiate denuclearization of the Korean peninsula in his highest-stakes foreign policy effort yet.

Trump made a point of publicly thanking North Korea's leader for the prisoners' release and hailed it as a sign of cooling tensions and growing opportunity on the Korean peninsula. Kim decided to grant amnesty to the three Americans at the "official suggestion" of the U.S. president, said North Korea's official news agency, KCNA.

North Korea had accused the three Korean-Americans of anti-state activities. Their arrests were widely seen as politically motivated and had compounded the dire state of relations over the isolated nation's nuclear weapons.

We are happy for the hostages and their families. We miss Otto. - Family of Otto Warmbier

Trump entered office as an emboldened North Korea developed new generations of nuclear weapons and ballistic missiles capable of hitting the continental U.S. Those advances were the subject of U.S. President Barack Obama's starkest warning shortly before Trump took office, and this is a crisis he's convinced his negotiating skills can resolve.

Crediting himself for recent progress, Trump has pointed to Kim's willingness to come to the negotiating table as validating U.S. moves to tighten sanctions — branded "maximum pressure" by the president.

The three were the latest in a series of Americans who have been detained by North Korea in recent years for seemingly small offences and typically freed when senior U.S. officials or statesmen personally visited to bail them out.

The last American to be released before this, college student Otto Warmbier, died in June 2017, days after he was repatriated to the U.S. with severe brain damage.

American student Otto Warmbier, centre, is escorted at the Supreme Court in Pyongyang, North Korea, on March 16, 2016. The young Ohioan was detained in North Korea for more than a year and died soon after being released. (Jon Chol Jin/Associated Press )

Warmbier was arrested by North Korean authorities in January 2016, accused of stealing a propaganda poster and sentenced to 15 years in prison with hard labour. His parents, Fred and Cindy Warmbier, have filed a wrongful death lawsuit, accusing the government of torturing and killing their son.

"We are happy for the hostages and their families," the Warmbiers said in a statement Wednesday. "We miss Otto."

Pence told CBS that he spoke on Wednesday with the Warmbier's family.

"I simply let them know that while we received this news with joy, that Otto was on all our hearts and the family was in our prayers," Pence said. "We got Otto home the last year, but it wasn't soon enough."

After the release of the detainees Thursday, North Korea's state-run media explicitly mentioned plans for the summit for the first time. Pyongyang has been exceptionally cautious about its public framing of Kim's recent diplomatic moves, which are a major shift from the more aggressive focus on missile launches and nuclear development that heated tensions to a boil last year.