The leader of Nippon Ishin Japan Innovation Party has announced that he plans to step down from his post.

Matsui Ichiro spoke to reporters on Sunday evening as votes were being counted after the Upper House election.

He said his party's performance in the election was not as good as he had hoped, although his party is projected to add seats to its pre-election strength.

Matsui had already said he would retire from politics completely after his term as Osaka mayor ends in April 2023.

He said the main governing Liberal Democratic Party was overwhelmingly powerful, but the party's politics is old and doesn't work when Japan is facing a population decline and aging society.

He said Japan needs reforms to create a sustainable society, and he wants the lawmakers of his party to confront the LDP.

Deputy party head Yoshimura Hirofumi expressed gratitude for Matsui for having led the party.

Yoshimura said he won't run in the leadership election. He said he intends to focus on his job as Osaka governor.