New Delhi, Feb. 12 -- South Korea's National Intelligence Service (NIS) has informed lawmakers that Kim Jong Un's teenage daughter is likely being positioned as North Korea's future leader, signaling a potential extension of the Kim family dynasty into a fourth generation.

In a closed-door briefing, NIS officials said they are closely monitoring whether Kim's daughter, believed to be Kim Ju Ae and around 13 years old, appears alongside her father at the upcoming Workers' Party Congress, lawmaker Lee Seong Kweun told reporters.

"In the past, NIS described Kim Ju Ae as being in the midst of 'successor training.' What was notable today is that they used the term 'successor-designate stage,' a shift that's quite significant," Lee said.

The...