The loss on Sunday left the Liberal Democrats a minority party in both houses of Parliament, while two new nationalist parties surged.

TOKYO -- The day after the drubbing of the ruling Liberal Democratic Party in Sunday's upper house election, Japanese Prime Minister Shigeru Ishiba struggled to contain party lawmakers increasingly critical of his decision to stay on.

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.