Kim Yong Chol, vice chairman of the central committee of the Korean Workers' Party, was seen at the international airport in Beijing, after arriving on a Koryo Air flight from Pyongyang, South Korean news service News 1 reported Tuesday.
Kim, who visited the South during the 2018 Pyeongchang Winter Olympics, is often linked to the 2010 sinking of the South Korean warship Cheonan.
The North Korean official was confirmed to be on flight CA981 bound for New York. The plane departed Beijing at 1 p.m. on Tuesday, local time.
Kim is likely to meet with Pompeo on Wednesday at an undisclosed location.
The meeting could take take place in New York, given movement restrictions for North Korean officials in the United States.
Kim is a veteran negotiator. According to News 1, Kim became notorious after an inter-Korea summit in 1991, when he would frequently smile for the cameras, but in private would engage in verbally abusive behavior.
South Korean newspaper Segye Ilbo reported Tuesday Kim was seen accompanied by Choe Kang Il, North Korean deputy chief for North American affairs.
North Korean movements are being reported as U.S. officials were seen in Seoul and Panmunjom, conducting working-level talks with the North Koreans over the weekend.
The Korea Times reported Tuesday U.S. Ambassador to the Philippines Sung Kim met with North Korea's vice foreign minister Choe Son Hui at Panmunjom on Sunday, but Sung Kim did not meet with the North Koreans on Monday or Tuesday.
Sung Kim was seen leaving a hotel in Seoul on Tuesday with Alison Hooker, a member of the White House National Security Council and Randall Shriver, Department of Defense assistant secretary for Asian and Pacific security affairs.