A poor showing by the coalition could shake investor confidence in the world’s fourth-largest economy and disrupt critical trade talks with the United States, analysts say.

Japan’s ruling coalition is likely to lose its majority in the upper house, exit polls showed after Sunday’s election, potentially heralding political turmoil as a tariff deadline with the United States looms.

Japan's leader Shigeru Ishiba faces mounting political pressure as his ruling coalition is set to lose its majority in the House of Councilors on Sunday.