North Korea appears to have entered the stage of designating leader Kim Jong-un's daughter Ju-ae as the successor, the spy agency was quoted as saying by lawmakers Thursday, marking a stepped-up assessment from its earlier evaluation of her as the "most likely successor."

Axar.az informs, citing Yonhap, the National Intelligence Service (NIS) shared the assessment during a closed-door briefing to the parliamentary intelligence committee, Reps. Park Sun-won and Lee Seong-kweun told reporters.

"As Kim Ju-ae has shown her presence at various events, including the founding anniversary of the Korean People's Army and her visit to the Kumsusan Palace of the Sun, and signs have been detected of her voicing her opinion on certain state policies, the NIS believes she has now entered the stage of being designated as successor," Lee said.

Lee said the latest assessment marked a step forward from the agency's previous views when it described Ju-ae as being "trained" to become a successor, to now assessing her as being at the stage of "successor designation."