Prime Minister Fumio Kishida is set to retain core figures in a planned Cabinet and ruling party executive reshuffle in the first half of September, as he works to establish a long-term administration, according to government sources.

Chief Cabinet Secretary Hirokazu Matsuno, Liberal Democratic Party Vice President Taro Aso and LDP Secretary General Toshimitsu Motegi are among those expected to retain their posts after the party's sweeping victory in the July 10 Upper House election, the sources said.

The LDP's strong showing in the House of Councilors election has put Kishida in a position to oversee a three-year period of stability in which no national elections will be held unless he dissolves the House of Representatives, the more powerful lower chamber of parliament.