Japanese Prime Minister Shigeru Ishiba said Monday he will stay in office to tackle challenges such as rising prices and high U.S. tariffs after a weekend election defeat left his coalition with a minority in both parliamentary chambers and triggered calls for his resignation.

Japan's Prime Minister Shigeru Ishiba faces an increasingly uphill battle in Sunday's upper house election, and a loss could worsen political instability at a time of daunting challenges, such as rising prices and high U.

Ishiba's ruling Liberal Democratic Party and its junior coalition partner Komeito were short three seats to maintain a majority in the 248-seat upper house in Sunday's vote.