Shiga Gov. Yukiko Kada officially declared Friday she will step down as head of the small political group Nippon Mirai no To (Tomorrow Party of Japan), apologizing to her constituents "for having caused worries" and pledging to "solely focus" on her gubernatorial duties.

Kada made the announcement while delivering a new year speech before Shiga prefectural employees. According to the text released, Kada said she has "taken seriously to heart" a recent resolution adopted by the prefectural assembly that urged her to quit as leader of Nippon Mirai, the splinter group she remained in charge of following the antinuclear party's crushing defeat in the Dec. 16 general election and subsequent breakup.

"I stood up (to become the group's head) for the sake of safety and the security (of people in and around) Shiga Prefecture and Lake Biwa, which have been exposed to high risks from nuclear power plants," Kada said. "But as a result, I have caused worries to Shiga residents, which I apologize for."