(CNN) North Korea's lead negotiator in nuclear talks with the United States, Kim Yong Chol, is expected to arrive in Washington by the weekend, a potential sign the two countries are getting closer to finalizing plans for a second summit between President Donald Trump and Kim Jong Un.

Kim Yong Chol, Pyongyang's former spymaster who has served as Secretary of State Mike Pompeo's counterpart in talks with the United States, is expected to arrive in the US capital Thursday and spend the night there, according to two US sources familiar with the negotiations.

Kim is then expected meet Pompeo and US special representative to North Korea Steve Biegun on Friday, the sources said.

It's unclear if he will visit the White House, but the sources say that is the expectation from the North Koreans and the US side is preparing for the possibility.

The dates for meetings between North Korea's top negotiator and US officials in Washington have only been confirmed to CNN by the US side. A source familiar with US-North Korea denuclearization talks told CNN that the meetings will happen "by this weekend." No firm details have been publicly announced yet.

Read More