North Korea's interlocutor leading negotiations with the United States on Tuesday arrived in Beijing en route possibly to Vietnam for talks with his U.S. counterpart ahead of next week's highly anticipated U.S.-North Korea summit in the Southeast Asian country.

Kim Hyok Chol, North Korea's former envoy to Spain, flew out of Pyongyang in the morning and is expected to stay the night in the Chinese capital.

He will likely be meeting with Stephen Biegun, U.S. special representative for North Korea, for their second round of working-level talks to finish laying the groundwork for the Feb. 27-28 summit in Hanoi. The first round was held earlier this month in Pyongyang.

At their historic first summit in Singapore on June 12, 2018, U.S. President Donald Trump and Kim Jong Un agreed that Washington would provide security guarantees to Pyongyang in return for "complete denuclearization" of the Korean Peninsula.

But U.S.-North Korea negotiations have shown little sign of moving forward against the backdrop of the Trump administration's skepticism about Pyongyang's intention to give up nuclear weapons.

In an interview with CBS on Feb. 13, U.S. Secretary of State Mike Pompeo said the U.S. administration seeks to make "real progress" on each of the points that Trump and Kim Jong Un agreed on in Singapore.

As part of a roadmap to denuclearization, the U.S. side is believed to be mulling concrete steps such as the dismantlement of North Korea's Yongbyon nuclear complex and preceding inspections, verification of the closure of its Punggye-ri Nuclear Test Site, and the shuttering of the Sohae missile engine test site.

As North Korea continues to refuse to declare its inventory of nuclear weapons and ballistic missiles, it remains unknown if a way can be found to bridge their differences.

The United States and North Korea have also been at odds over whether international economic sanctions, aimed at preventing Pyongyang's nuclear weapon and ballistic missile development programs, should be lifted.

Kim Jong Un, who has recently pledged to revitalize the nation's economy rather than bolstering its arms capability, is likely to ask Trump to ease the sanctions next week, with North Korea arguing it has already started to take concrete steps toward denuclearization.

Pyongyang also will likely stress measures such as the suspension of U.S.-South Korean military exercises around the Korean Peninsula.

Washington and Pyongyang remain technically at war as the 1950-1953 Korean War ended in a cease-fire.

In the war, U.S.-led multinational forces fought alongside South Korea against the North, backed by China and the Soviet Union. Hostilities ceased with an armistice agreement signed in July 1953 by the U.N. Command, North Korea's military and Chinese armed forces.

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