Japanese political parties are divided over a proposal to reduce the number of seats in the House of Representatives [1].
The dispute centers on how to shrink the legislature to reform the electoral system. While some see it as a necessary step for efficiency, others argue that targeting specific seat types undermines political trust and fairness.
The plan was introduced during the autumn extraordinary Diet session, which concluded on Dec. 17, 2025 [5]. Under the terms of the proposal, if a final agreement is not reached within one year, a reduction of 45 seats from the proportional representation block will be automatically applied [1]. This block currently consists of 176 seats [1].
Representatives from the Liberal Democratic Party (LDP) and the Nippon Ishin no Kai have expressed a general policy to reduce the total number of seats by approximately 10 percent, or about 45 seats [4]. However, the specific composition of these cuts remains a point of contention. Some reports suggest the reduction would target only proportional seats [1], while other plans include a mix of 25 single-seat constituencies and 20 proportional seats [4].
"I believe that the reduction of the number of seats in the current Diet session must be carried out," Yoshimura said [1].
Opposition parties, including the Constitutional Democratic Party, the Komeito, and the Center Reform Union, have reacted strongly against the measure. Takeshi Kai, secretary-general of the Center Reform Union, questioned the logic of the proposal, asking, "Why reduce only the proportional seats?" [1].
Internal friction has also emerged within the LDP. Former Foreign Minister Takeshi Iwaya expressed concern that predetermining a cut specifically to proportional seats could damage political relationships. "Deciding in advance to reduce only the proportional seats... may risk breaking the relationship of trust," Iwaya said [1].
The total number of seats in the House of Representatives currently stands at 465 [2].
“"I believe that the reduction of the number of seats in the current Diet session must be carried out,"”
The conflict highlights a strategic struggle over the structure of Japanese representation. Because proportional representation seats often benefit smaller or minority parties more than single-seat districts, a targeted cut to the proportional block could disproportionately shrink the influence of opposition parties while preserving the dominance of the LDP in local districts.
