North Korean leader Kim Jong-un's half-sister Kim Sol-song has taken charge of the Workers Party secretariat, whose duties include taking care of Kim Jong-un's day-to-day schedules and protecting him, an expert claimed Wednesday.

She takes over the job from their aunt Kim Kyong-hui, the widow of executed eminence grise Jang Song-taek.

Ken Gause of the U.S. Center for Naval Analyses made the claim in an interview with Radio Free Asia. He added that Kim Sol-song has become a key adviser to the North Korean leader. That would put her at the apex of the organization that controls information flow, he said, and is training Kim Jong-un's younger sister Yo-jong, who will replace her sometime in the future.

Gause speculated that the regime is stable for the time being.

