U.S. arms control chief John Bolton expressed understanding Friday for the belief among the families of Japanese abducted by North Korea that a regime change is necessary in Pyongyang, a representative of a group for the families said.

Bolton, undersecretary of state for arms control and international security, met with representatives of the group at the U.S. State Department, Yoichi Shimada told reporters.

Members of the group are visiting the United States, including Takuya Yokota, whose younger sister Megumi was abducted at age 13, and Shigeo Iizuka, whose younger sister Yaeko Taguchi was abducted aged 22.