Core Viewpoint - The Japanese ruling party, the Liberal Democratic Party (LDP), and the largest opposition party, the Constitutional Democratic Party, have reached an agreement to hold a prime ministerial election on October 21, following the recent election of Sanna Takashi as the LDP president [1] Group 1: Political Developments - The temporary Diet session will take place from October 21 to December 17 [1] - Sanna Takashi's election as LDP president on October 4 is a prerequisite for the prime ministerial election [1] - The Cabinet Secretary Yoshihide Suga announced the temporary Diet session on October 15, but there was initially no agreement on the election date [1] Group 2: Economic Measures - If Sanna Takashi is elected as prime minister, she plans to implement economic measures to curb rising prices [1] - A supplementary budget for the fiscal year 2025 is expected to be submitted to the Diet for review in early December [1] Group 3: Election Process - The prime ministerial election will occur in both houses of the Diet, with a majority vote required to win in the first round [1] - If no candidate receives a majority, the top two candidates will proceed to a second round of voting [1]