Former foreign minister Toshimitsu Motegi is the first ruling party MP to throw his hat into the ring to succeed outgoing Japanese Prime Minister Shigeru Ishiba, as financial markets whipsaw on the political uncertainty.

Ishiba called time on his brief tenure on Sunday, saying he was taking responsibility for bruising elections in which his ruling coalition lost its majority in both houses of parliament amid voter anger over rising living costs.

He instructed his Liberal Democratic Party (LDP) - which has governed Japan for most of its postwar history - to hold an emergency leadership election.

The party planned to hold the vote on October 4, broadcaster TBS reported.

Japan's yen sank and stocks surged on Monday after Ishiba's resignation stoked speculation that his potential successor

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