Trump to meet Kim Jong Un in Singapore for summit

President Donald Trump announced on Twitter on Thursday that a highly anticipated meeting with Kim Jong Un will take place in Singapore on June 12th.

The announcement comes on the heels of the release of three American prisoners who had been detained for more than a year in North Korea. The three men, Kim Dong Chul, Kim Hak Song and Kim Sang Duk, also known as Tony Kim, met with President Trump early Thursday morning after landing at Joint Base Andrews in Maryland.

Earlier in the week, newly-minted Secretary of State Mike Pompeo made his second trip to North Korea, laying the groundwork for a summit between Trump and North Korea's Kim Jong Un. He was the second sitting secretary of state to visit the reclusive nation and the highest-ranking U.S. official to meet the young North Korean leader.

U.S. officials had made it clear to their North Korean counterparts that the Americans' release was paramount.

Earlier Thursday morning, during his remarks on the tarmac Trump praised North Korea's leader saying, "We want to thank Kim Jong Un, who was really excellent to these incredible people."

"The fact we were able to get them out so soon was a tribute to a lot of things," said Trump, standing on the tarmac at Joint Base Andrews in Maryland, "I just want to say, this is a special night."

When asked by ABC's Jonathan Karl why he thought Kim Jong-un decided to free the prisoners now, Trump replied: "I think he did this because I really think he wants to do something and bring that country into the real world. I really believe that Jon," Trump said. "I think that we're gonna have a success. I think this will be a very big success."

Kim Dong Chul, a South Korean-born U.S. businessman and pastor, is the longest-known U.S. detainee in North Korea, having spent at least 900 days in custody. He was arrested in October 2015.

Pyongyang alleged that Chul was arrested after he attempted to connect with and receive classified information from a former North Korean soldier. North Korea said he was colluding with the South Korean spy agency, which denied being involved with Kim.

He was sentenced in April 2016 to 10 years of hard labor.

The two other detainees, Kim Hak Song and Tony Kim, worked at the Pyongyang University of Science and Technology.

They were detained in 2017 and charged with "hostile acts" against the North Korean state.

The men released a statement through the State Department: "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. 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."

Trump, surrounded by journalists and cameras earlier on Thursday also teased the "highly anticipated meeting."

"We have a meeting scheduled in a very short period of time. We have the location set," he said. "We'll see if we can do something that people did not think was going to happen for many, many years."

He added, "My proudest achievement will be, this is part of it, but will be when we denuclearize that entire peninsula."

ABC News' Karson Yiu, Meghan Keneally, Jordyn Phelps, and Conor Finnegan contributed to this report.

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