* Biden, Kishida reaffirm U.S.-Japan alliance
* Foreign minister Motegi says Japan to weigh Taiwan scenarios
* Kishida appoints economic security minister with China in mind
* Tensions over Taiwan, China could dominate Kishida's tenure (Recasts throughout, adds Kobayashi quotes)
By Sakura Murakami and Kiyoshi Takenaka
TOKYO, Oct 5 (Reuters) - New Japanese Prime Minister Fumio Kishida on Tuesday affirmed Tokyo's alliance with Washington and signalled concerns about China's posture over Taiwan, his foreign minister saying Japan would "consider options" and prepare for "various scenarios".
Taiwan and broader relations with Beijing are likely to dominate security policies and foreign relations from the outset of Kishida's tenure, and could emerge as a key issue in the upcoming general election, analysts say.
Underscoring the new cabinet's China focus, Kishida created a new post of economy security minister, filled by an official who helped craft policies aimed at protecting sensitive technologies in supply chains and cyber security from China.
Asked about Taiwan, which has reported 148 flights https://www.reuters.com/business/aerospace-defense/taiwan-reports-largest-ever-incursion-by-chinese-air-force-2021-10-02 by Chinese military planes into its air defence identification zone since Friday, Foreign Minister Toshimitsu Motegi said he hoped "this matter is resolved peacefully between the two parties through direct talks."
"Additionally, instead of simply monitoring the situation, we hope to weigh the various possible scenarios that may arise to consider what options we have, as well as the preparations we must make," Motegi said.
Kishida's retaining of Motegi, along with Defence Minister Nobuo Kishi, signalled his desire to continue ex-Prime Minister Shinzo Abe's push to boost security ties with the US while preserving trade relations with China, analysts say.
Kishida, a former foreign minister, on Monday unveiled a cabinet lineup https://www.reuters.com/world/asia-pacific/key-policies-japans-next-pm-kishida-consensus-builder-2021-09-29 mixing allies of Abe and ex-Finance Minister Taro Aso in key posts with relative political novices, in keeping with his promise to give younger lawmakers a chance.
Shortly after being formally confirmed by the parliament in the top job, the 64-year-old Hiroshima native surprised the opposition by calling an election for Oct. 31 and vowed to bolster the country's response to the coronavirus pandemic.
Kishida told reporters on Tuesday morning in Tokyo he had received a "strong" message from President Joe Biden about the United States' commitment to defending the disputed East China Sea islets known as the Senkaku Islands in Japan. China also claims the islands, which it calls the Daioyus.
In phone conversation that lasted roughly 20 minutes, the allies also confirmed their cooperation toward achieving a free and open Indo-Pacific, Kishida told reporters.
Kishida, who is from a traditionally dovish faction of the ruling Liberal Democratic Party (LDP), had tacked to the right as he campaigned to be the party's leader, reflecting a broader shift in the LDP spurred by Abe's record-long tenure.
Kishida has said that acquiring the ability to strike enemy bases, a controversial step backed by Abe, was a viable option and that he would appoint an aide to monitor China's treatment of its Uyghur minority. China denies accusations of abuse.
The new prime minister is also expected to deepen engagement with the United States, Australia, India and Japan - known as the Quad - which Beijing sees as an effort to contain its rise.
His economic security minister is 46-year-old Takayuki Kobayashi, a graduate of Harvard's Kennedy School and Tokyo University, who has worked closely on economic security policies with the new secretary general of the LDP, Akira Amari, another Abe ally.
In his first news conference, Kobayashi aimed to strike a balance between pressuring China and maintaining good relations, saying the ties were of great importance to both countries.
"At the same time, I also think it's important for the further development of the global economy that China, as an economic superpower, complies with the rules of the international community and fulfils its responsibilities in a way that is fit for a large country," Kobayashi said.
(Reporting by Chang-Ran Kim, Antoni Slodkowski, Kiyoshi Takenaka and Sakura Murakami; Editing by Muralikumar Anantharaman and Gerry Doyle)
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