Questions loom over progress with North Korea

A soldier carries a casket containing the remains of a US soldier killed during the 1950-53 Korean War, after arriving from North Korea at Osan Air Base in Pyeongtaek on July 27, 2018. - A US military aircraft carrying the remains of US Korean War dead collected in North Korea arrived in the South on July 27, the 65th anniversary of the armistice that ended the fighting. (Photo by KIM HONG-JI / POOL / AFP) (Photo credit should read KIM HONG-JI/AFP/Getty Images)

Questions loom over progress with North Korea

Situation Room

The delay in returning what is believed to be the remains of US troops killed during the Korean War has some worried about the more contentious negotiations with North Korea over denuclearization. CNN's Will Ripley reports.

02:34 - Source: CNN

President Donald Trump and North Korea 16 videos

A soldier carries a casket containing the remains of a US soldier killed during the 1950-53 Korean War, after arriving from North Korea at Osan Air Base in Pyeongtaek on July 27, 2018. - A US military aircraft carrying the remains of US Korean War dead collected in North Korea arrived in the South on July 27, the 65th anniversary of the armistice that ended the fighting. (Photo by KIM HONG-JI / POOL / AFP) (Photo credit should read KIM HONG-JI/AFP/Getty Images)

Questions loom over progress with North Korea

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US Secretary of State Mike Pompeo (3rd L) shakes hands with North Korea's Foreign Minister Ri Yong Ho (3rd R) as they arrive for a group photo at the ASEAN Regional Forum Retreat during the 51st Association of Southeast Asian Nations (ASEAN) Ministerial Meeting (AMM) in Singapore on August 4, 2018. - Leaders, ministers and representatives are meeting in the city-state from August 1 to 4 for the ASEAN Ministerial Meeting (AMM). (Photo by Mohd RASFAN / AFP) (Photo credit should read MOHD RASFAN/AFP/Getty Images)

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TOPSHOT - US President Donald Trump (R) poses with North Korea's leader Kim Jong Un (L) at the start of their historic US-North Korea summit, at the Capella Hotel on Sentosa island in Singapore on June 12, 2018. - Donald Trump and Kim Jong Un have become on June 12 the first sitting US and North Korean leaders to meet, shake hands and negotiate to end a decades-old nuclear stand-off. (Photo by SAUL LOEB / AFP) (Photo credit should read SAUL LOEB/AFP/Getty Images)

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TOPSHOT - North Korea's leader Kim Jong Un (L) shakes hands with US President Donald Trump (R) after taking part in a signing ceremony at the end of their historic US-North Korea summit, at the Capella Hotel on Sentosa island in Singapore on June 12, 2018. - Donald Trump and Kim Jong Un became on June 12 the first sitting US and North Korean leaders to meet, shake hands and negotiate to end a decades-old nuclear stand-off. (Photo by Anthony WALLACE / POOL / AFP) (Photo credit should read ANTHONY WALLACE/AFP/Getty Images)

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TOPSHOT - US President Donald Trump (R) poses with North Korea's leader Kim Jong Un (L) at the start of their historic US-North Korea summit, at the Capella Hotel on Sentosa island in Singapore on June 12, 2018. - Donald Trump and Kim Jong Un have become on June 12 the first sitting US and North Korean leaders to meet, shake hands and negotiate to end a decades-old nuclear stand-off. (Photo by SAUL LOEB / AFP) (Photo credit should read SAUL LOEB/AFP/Getty Images)

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SINGAPORE, SINGAPORE - JUNE 12: In this handout photograph provided by The Strait Times, North Korean leader Kim Jong-un (L) with U.S. President Donald Trump (R) during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore. U.S. President Trump and North Korean leader Kim Jong-un held the historic meeting between leaders of both countries on Tuesday morning in Singapore, carrying hopes to end decades of hostility and the threat of North Korea's nuclear programme. (Photo by Kevin Lim/The Strait Times/Handout/Getty Images)

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SINGAPORE - JUNE 12: In this handout photo, North Korean leader Kim Jong-un shakes hands with U.S. President Donald Trump during their historic U.S.-DPRK summit at the Capella Hotel on Sentosa island on June 12, 2018 in Singapore. U.S. President Trump and North Korean leader Kim Jong-un held the historic meeting between leaders of both countries on Tuesday morning in Singapore, carrying hopes to end decades of hostility and the threat of North Korea's nuclear program. (Photo by Kevin Lim/THE STRAITS TIMES/Handout/Getty Images)

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U.S. Secretary of State Mike Pompeo, second from right, greets Kim Yong Chol, second from left, a North Korean senior ruling party official and former intelligence chief, as they arrive for a meeting at the Park Hwa Guest House in Pyongyang, North Korea, Friday, July 6, 2018. Pompeo is on a trip traveling to North Korea, Japan, Vietnam, Abu Dhabi, and Brussels. Also pictured is Andrew Kim, the head of the CIA's Korea Mission Center, right. (AP Photo/Andrew Harnik, Pool)

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