Japanese Prime Minister Shigeru Ishiba has decided to step down following mounting pressure from within his ruling party after a major electoral setback that cost the coalition its majority in both houses of parliament, Japanese media reported Sunday.

Public broadcaster NHK said Ishiba’s decision aimed to avoid a damaging party split, while the Asahi Shimbun daily noted he could not withstand growing calls for his resignation.

Ishiba, who took office in October last year, had resisted stepping down for more than a month despite repeated demands, largely from right-wing rivals in his party.

His departure sets the stage for a party leadership contest to choose a successor, as Japan faces political uncertainty and domestic economic challenges.