TOKYO– Defiant but finding himself increasingly isolated within the ruling Liberal Democratic Party (LDP), Japan’s Prime Minister Shigeru Ishiba said on Sept 7 that he was calling time on a short-lived tenure.

Mr Ishiba, who is

resigning as LDP president

, will remain in office as prime minister until a successor is chosen. His decision was made to stave off a simmering civil war within the party.

Mr Ishiba said that with US President Donald Trump having signed off on an executive order over Japan’s trade deal on Sept 4, “a turning point has been reached”.

“I have always said that I am not attached to my position, and that I will make a decision at the appropriate time,” he told a nationally televised news conference.

“As president, I bear responsibility for the election results. Now that negotiations regarding US tariff measures have reached a conclusion, I believe that this is the appropriate time to step down.”

The party blamed Mr Ishiba for three straight electoral drubbings since he took office on Oct 1, 2024 – the Lower House election in October 2024, a Tokyo Metropolitan Assembly poll in June 2025, and then an Upper House election the following mon th.

The LDP now leads a minority government with its coalition partner Komeito, and requires the cooperation of other opposition parties to pass legislation in the Diet.

While Mr Ishiba had resisted calls to quit, the straw that broke the camel’s back appeared to be a party decision to hold a majority vote among its elected lawmakers and prefectural representatives on whether a snap party leadership election should be held.

He had reportedly floated the idea of calling a high-stakes snap election instead, as public opinion had turned the tide in his favour since August, but threw in the towel as his rivals within the LDP agitated for his removal.

His resignation will trigger a party presidential election race, where leading contenders include Agriculture Minister Shinjiro Koizumi, 44; and former economic security minister Sanae Takaichi, 64.

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