Seoul’s Ministry of Unification also did not provide any reason for her absence, with an official saying there was “no information” on the matter.

Considering Kim’s past involvement and role in US-North Korea nuclear negotiations, experts say she might have “too much on her plate” at the moment.

“Kim may be preparing for tasks related to Washington-Pyongyang dialogue and the possible second US-North Korea summit,” said Yang Moo-jin, a professor at the University of North Korean Studies.

Echoing Yang’s remarks, Rep. Lee Hae-chan, chief of the ruling Democratic Party, said at an event held at the National Assembly on Thursday that it seems Kim’s absence is due to preparations for a high-level meeting between Washington and Pyongyang, and saw it as a positive sign of progress in nuclear talks.

Kim was spotted alongside Vice Chairman of the North’s ruling Workers’ Party Central Committee Kim Yong-chol during his trip to the US in May, prior to the first US-North Korea summit in Singapore in June. She also accompanied Kim Yo-jong, North Korean leader Kim Jong-un’s younger sister, on her trip to South Korea in February as part of a delegation to the PyeongChang Olympics.

Kim Song-hye might also be deeply involved in other diplomatic activities. Japan’s Fuji News Network reported Tuesday that she secretly met with Shigeru Kitamura, chief of Japan’s Cabinet Intelligence and Research Office, in Mongolia last week, citing multiple sources within the Japanese government.

However, Korean media outlet Joongang Ilbo claimed Wednesday that the meeting failed to take place, citing a source in Japan familiar with the matter.

Analysts also noted that the North might have removed her from the delegation list, as key officials in the South involved in inter-Korean affairs are currently abroad. President Moon Jae-in began his ASEAN and APEC trips on Tuesday, while Unification Minister Cho Myoung-gyon is in the US to meet with US lawmakers and attend forums.

Though the Seoul government said it has no plans to meet with the North Korean officials, there have been rumors that they might meet behind closed doors. Gyeonggi Province has been eyeing cross-border projects with the North, including opening a South Korean branch of Pyongyang’s famous restaurant Okryugwan.

Meanwhile, the North Korean officials led by Ri Jong-hyok, vice chairman of the Korean Asia-Pacific Peace Committee, will stay at the MVL Hotel in Goyang, Gyeonggi Province, until Saturday, according to officials at the Gyeonggi provincial government. Gyeonggi Province is co-sponsoring the forum with the Asia-Pacific Exchange Association, a Seoul-based private foundation.

Ri held a meeting with Gyeonggi Province Gov. Lee Jae-myung on Thursday, and the two visited the Second Techno Valley in the Pangyo district of Gyeonggi Province’s city of Seongnam, known as the South Korean version of Silicon Valley. They participated in a test-ride of a self-driving vehicle.

Ri was to meet with Rep. Lee Hae-chan over dinner.

By Jung Min-kyung (mkjung@heraldcorp.com)