South Korean President Moon Jae-in has urged Trump and Kim to try harder to achieve a breakthrough in their nuclear negotiations, while Trump suggests disarmament will take longer than anyone will like

President Donald Trump has tweeted a letter to him from North Korean leader Kim Jong Un heralding "epochal progress" in U.S.-North Korea relations

ABC News' Tara Palmeri traveled with Mike Pompeo in North Korea last week.

Trump told reporters Tuesday he has another "little gift" for Kim as well.

President Trump told reporters Tuesday that he has another "little gift" for Kim as well.

President Donald Trump says Secretary of State Mike Pompeo didn't deliver Trump's gift of an autographed Elton John CD to North Korean leader Kim Jong Un on his trip this week

President Trump voiced confidence that North Korea's leader would "honor" his commitment to denuclearize, despite Pyongyang's assertion that the US is making "gangster-like" demands in negotiations.

President Donald Trump has voiced confidence that North Korea's leader would "honor" his commitment to denuclearize

U.S. Secretary of State Mike Pompeo held tough talks with North Korean officials, who afterward accused the U.S. of making "gangster-like" demands.

Mike Pompeo tells North Korean officials if they think his demands are "gangster-like," he's got plenty of company.

Secretary of State Mike Pompeo responds to tough negotiations with North Korean top officials.

Just before leaving Pyongyang, Secretary of State Mike Pompeo said the meeting was productive and that steps towards denuclearization are being made.

Secretary of State Pompeo met with North Korean officials Friday and Saturday.

Secretary of State Mike Pompeo met with North Korean counterparts for nearly three hours in Pyongyang Friday. The meeting was low on details.

Sec. Mike Pompeo goes to Pyongyang to continue to push for denuclearization of the peninsula.

There are fresh doubts about whether North Korea will follow through on the commitment it made at President Trump and Kim's Singapore summit.

There are fresh doubts about whether North Korea will follow through on the commitment it made at President Trump and Kim's Singapore summit.

The two Koreas are getting together to determine 100 families for reunions.

What demands is Pompeo taking to Pyongyang Thursday amid growing doubts about North Korea's commitment to denuclearization?

Dozens of South Korean basketball players arrive in Pyongyang for a series of games to foster a mood of detente generated by the recent North-South summits

New satellite imagery shows North Korea expanding a ballistic missile plant.

An American delegation met with their North Korean counterparts in Panmunjom in the Demilitarized Zone between North and South Korea on Sunday, a State Department spokesperson confirmed to ABC News.

The U.S. met to discuss how to proceed following Trump's summit.

President Donald Trump's national security adviser says the U.S. has a plan that would lead to the dismantling of North Korea's nuclear weapons and ballistic missile programs in a year

The Olympic Council of Asia said North and South Korea will field combined teams in canoeing, rowing and women's basketball at the Asian Games in August in Indonesia

U.S. Defense Secretary Jim Mattis and Chinese leaders have struck a largely positive public tone despite security tensions and an impending trade war

The Koreas are charging ahead, taking advantage of the momentum for peace and cooperation agreed upon by their respective governments.

In another sign of detente following Donald Trump's summit with Kim Jong Un, North Korea isn't holding the annual "anti-U.S. imperialism" mass rally marking the start of the Korean War

North and South Korea have agreed to hold temporary reunions of families divided by the 1950-53 Korean War as they boost reconciliation efforts amid a diplomatic push to resolve the North Korean nuclear crisis

On the North Korean side of the Demilitarized Zone, the sound of silence is a welcome sign of detente

In their third meeting in less than three months, North Korean leader Kim Jong Un and Chinese President Xi Jinping reportedly hailed their close and growing ties.

South Korea's president has urged North Korea to present a plan with concrete steps toward denuclearization, raising the pressure on North Korean leader Kim Jong Un during his visit to Beijing

Chinese President Xi Jinping has told North Korean leader Kim Jong Un he hopes Pyongyang and Washington can implement the outcome of last week's nuclear summit at which the sides agreed to work toward denuclearization in exchange for security guarantees

President Trump says he asked Kim Jong Un for the remains at last week's summit.

An ABC News/Washington Post poll found that fewer are skeptical of North Korea.

North Korean leader Kim Jong Un arrived in Beijing Tuesday morning for his third visit to China in less than three months just one week after the Singapore Summit.

North Korean leader Kim Jong Un arrived in Beijing Tuesday morning for his third visit to China in less than three months just one week after the Singapore Summit.

The president's former strategist said Trump is being unfairly criticized.

ABC News spoke with defectors with surprisingly different opinions.

President Trump told ABC News' George Stephanopoulos in an exclusive interview that North Korea will denuclearize, but critics say the agreement the two leaders signed still falls short.

Brutality in North Korean prisons "has no parallel," says a war crimes report.

North Korea is presenting President Donald Trump in a new, respectful light as a way to keep its people on board with the tectonic shifts in their country's relationship with the United States

The U.S. secretary of state said economic relief would come with North Korea's "full denuclearization."

Trump took to Twitter to reassure Americans to "sleep well tonight."

President Trump is facing backlash for his defense of Kim Jong Un's history of human rights abuses as more questions arise about the document they signed.

North Korea's state-run TV has aired its first video from the historic summit between its leader, Kim Jong Un, and U.S. President Donald Trump.

North Korea has aired its first video from Tuesday's unprecedented summit between its reclusive leader, Kim Jong Un, and U.S. President Donald Trump.

Secretary of State Mike Pompeo defended Trump's signed agreement with Kim Jong Un, which did not explicitly stipulate verification, ABC News' Janai Norman reports.