Donald Trump has confirmed the date and location of his historic meeting with Kim Jong-un - saying he will meet the North Korean leader in Singapore on June 12 and calling it a “very special moment for world peace!”

While earlier media reports had suggested the US and North Korea had opted for the South East Asian city state as the location for the meeting, Mr Trump's tweet was the first official announcement confirming speculation over the landmark summit. Other locations that had been considered were the demilitarised zone between North and South Korea, and the Mongolian capital of Ulan Bator.

“The highly anticipated meeting between Kim Jong-un and myself will take place in Singapore on June 12th,” Mr Trump wrote. “We will both try to make it a very special moment for world peace!”

Mr Trump had previously expressed a preference for the meetings to be held in the demilitarised zone, which he said would be an especially symbolic location to meet.

But reports suggested the White House was concerned the DMZ, which was recently the site of a meeting between Mr Kim and South Korean leader Moon Jae-in, might be seen as providing an advantage to the North Korean leader. As it is, Singapore is a strong US ally and the US Navy regularly visits the former British colony.

The announcement came just hours after Mr Trump scored a huge diplomatic and public relations victory, when he made a pre-dawn visit to Andrews Air Force Base near Washington to welcome home three Korean-Americans released by North Korea ahead of the meeting.

Mr Trump and the first lady, Melania Trump, boarded the medical plane the released detainees were on to speak privately before presenting them to the media outside.

North Korea Military Parade Show all 6 1 /6 North Korea Military Parade North Korea Military Parade In this image made from video released by KRT on Feb. 8, 2018, a military parade is held at Kim Il Sung Square in Pyongyang, Thursday, Feb. 8 2018, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade This screen grab taken from North Korea's KCTV on February 8, 2018 shows members of North Korea's military taking part in a parade, with missiles being displayed, in Kim Il Sung Square in Pyongyang. North Korea staged a military parade in Pyongyang on February 8 to mark the 70th anniversary of its armed forces, in a show of strength just a day before the Pyeongchang 2018 Winter Olympic Games open in the South. / AFP PHOTO / KCTV / KCTV / -----EDITORS NOTE --- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / KCTV" - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS - NO ARCHIVESKCTV/AFP/Getty Images AFP/Getty Images North Korea Military Parade In this image made from video released by KRT, North Korean soldiers march during a military parade in Pyongyang, Thursday, Feb. 8 2018. North Korea held a military parade and rally on Kim Il Sung Square on Thursday, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade In this image made from video released by KRT on Feb. 8, 2018, North Korean leader Kim Jong Un, right, inspects honor guards, along with his wife Ri Sol Ju, center, during a military parade in Pyongyang, Thursday, Feb. 8 2018. North Korea held a military parade and rally on Kim Il Sung Square on Thursday, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade In this image made from video released by KRT on Feb. 8, 2018, North Korean leader Kim Jong Un, center, watches the military parade in Pyongyang, Thursday, Feb. 8 2018. North Korea held a military parade and rally on Kim Il Sung Square on Thursday, just one day before South Korea holds the opening ceremony for the Pyeongchang Winter Olympics. (KRT via AP Photo) AP North Korea Military Parade This screen grab taken from North Korea's KCTV on February 8, 2018 shows North Korean leader Kim Jong Un speaking during a military parade in Kim Il Sung Square in Pyongyang. North Korea staged a military parade in Pyongyang on February 8 to mark the 70th anniversary of its armed forces, in a show of strength just a day before the Pyeongchang 2018 Winter Olympic Games open in the South. / AFP PHOTO / KCTV / KCTV / -----EDITORS NOTE --- RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / KCTV" - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS - NO ARCHIVESKCTV/AFP/Getty Images AFP/Getty Images

“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,” said a statement from the men.

“I appreciate Kim Jong-un doing this and allowing them to go,” Mr Trump told reporters at the White House ahead of their release. He also thanked the Chinese president, Xi Jinping, saying that Beijing had been “helpful” in securing the freedom of Kim Dong Chul, Kim Hak-song, and Kim Sang Duk.

Mr Trump’s meeting with Mr Kim will be the first time that a sitting American president has met with a leader of North Korea, and Mr Trump has said the pre-summit discussions with North Korea have been “serious and positive”.

The president has vowed to walk away from the table if he thinks that Mr Kim is negotiating in bad faith. In recent weeks, Mr Trump has cited Mr Kim’s willingness to negotiate as a sign that his tough approach towards North Korea earlier in his presidency – which he has referred to as a “maximum pressure” campaign – has worked.

White House Deputy Press Secretary Raj Shah said on Air Force One as the president was heading to Indiana for a political rally that would not be "getting into the conversations that [Mr] Pompeo had. What I will say is that, prior to the invitation being accepted several months ago or at least well over a month ago now, the North Koreans agreed to halt their ballistic missile testing, halt their nuclear testing, and not publicly oppose joint US-South Korean military exercises".

Mr Trump will "hold them to those steps," Mr Shah said, but did not elaborate on further possible pre-conditions for the 12 June summit.

The coming negotiations, which Mr Trump hopes will result in an end to North Korea’s nuclear weapons ambitions. "Our policy is to ensure the complete, irreversible, and verifiable denuclearisation of the Korean Peninsula," Mr Shah noted. And that’s what he’s going to be seeking". Mr Trump's role in brokering the summit has led to some claims that he should receive the Nobel Peace Prize.

“Everyone thinks so, but I would never say it,” Mr Trump said when asked about the rumour on Wednesday.

Mr Pompeo, who recently became secretary of state, has made at least two trips to meet with top North Korean officials, including Mr Kim.

Mike Pompeo meets Kim Jong-un in North Korea

Speaking to reporters after the prisoners were released, Mr Trump suggested that their release is a sign that the upcoming talks will be fruitful.

“I think he did it because I really think he wants to do something and bring that country into the real world. I really believe that,” Mr Trump said. “I think that we’re gonna have a success. I think this will be a very big success.”

Pyongyang has said the prisoners were detained for alleged spy activities. Kim Dong Chul was the longest serving prisoner, and spent at least 900 days in North Korean custody after his arrest in October 2015.