Prime Minister Shigeru Ishiba on Saturday hinted at the possibility of holding a snap election for the House of Representatives — the lower chamber of parliament — on the same day as next summer's election for the House of Councillors, the upper chamber.

"It's possible," Ishiba told a television program. "There's no rule that says (they) can't be held at the same time."

Ishiba, who heads a minority government, would not survive a no-confidence motion against his Cabinet if opposition parties table it together.