Japanese Prime Minister Shigeru Ishiba has suffered a major political setback as his ruling coalition failed to secure a majority in the upper house, leaving it in the minority in both chambers of parliament for the first time since 1955.

Japan’s ruling coalition is on track to lose its majority in the upper house, according to exit polls from Sunday’s election cited by Reuters. The development could spell heightened political instability just as the country nears a critical trade deadline with the United States.

TOKYO (AP) — 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.S. tariffs.