Koike, who became Tokyo's first female leader last year and led her local party to a stunning victory in July city elections, has launched a new national party, the Party of Hope, to challenge Prime Minister Shinzo Abe in the Oct. 22 parliamentary vote.
Koike told The Associated Press on Friday she wants to use her experience in Tokyo to encourage changes nationally, and is working with like-minded politicians to push for her goals. She says women's advancement and measures for Japan's aging and shrinking population have come too slowly under Abe.
"As Tokyo governor, I want to achieve policies in Tokyo as a model for entire Japan to follow. Why? Because it's faster that way," Koike said in an interview at the office of her local party, Tomin First no Kai, wearing a scarf with a blue-and-white Tokyo 2020 Olympics motif. "Everything takes too long in national politics."
She didn't make clear whether she plans to run for parliament or is seeking the prime ministership.
"God only knows," Koike, an expert on Middle East studies, said in Arabic.
Her political rivals have criticized her for switching between "two pairs of shoes" for local and national politics, but Koike says her dual approach is good for both, especially at a time when she needs to be a bridge between the city and central government in preparing for the Tokyo Olympics.
"By demonstrating our clear vision in specific policy measures in Tokyo, we can also make them happen in national politics," Koike said. "As a start, I plan to concentrate on creating a model in Tokyo. In order to do so, I need to change national politics."
A nuclear energy phase-out by 2030, discussions on changing Japan's pacifist constitution, and "realistic" defense policies under a new security law pushed through by Abe in 2015 to expand Japan's military role are some of her election positions.
Koike said she is preparing "sharp and clear" policies that will attract voters who are in the middle.
She said Abe is seen as too rightwing, while liberals are moving to the left. Comparing politics to a golf course, she said "the fairway is wide open." Koike said her Party of Hope aims to be reformist and mildly conservative.
Koike worked with Abe as a lawmaker in the ruling Liberal Democratic Party for 15 years. She served in key Cabinet and ruling party posts, including defense minister and environment minister, before becoming the leader of Japan's capital in July 2016. A TV newscaster-turned-politician, Koike is stylish and media savvy.
As Tokyo governor, she has advocated administrative reforms, reviewed plans for costly venues for the Tokyo 2020 Olympics to reduce city spending, suspended the divisive relocation of a famed fish market over safety concerns, and halved her salary.
Koike, however, has faced accusations from some that she hasn't actually achieved much, and running for parliament now would expose her to criticism that she is abandoning Tokyo before her work is done.
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