TOKYO - Prime Minister Sanae Takaichi entered the week of July 20 with her government facing a shortened but politically important stretch before the extended Diet session ends, as debate continued over Bank of Japan independence, domestic investment policy, the revised Imperial House Law and the ruling coalition’s unfinished legislative agenda.

July 20 was Marine Day, a national holiday in Japan, making it a quieter day for formal political activity. But the political agenda remained active because the Diet session, originally scheduled to end on July 17, has been extended until July 25. The extension gives the ruling bloc more time to move remaining bills, including legislation linked to the Japan Innovation Party’s priorities, while also prolonging scrutiny of Takaichi’s economic strategy.

The extension changes the political meaning of the Diet endgame. Last week, the government appeared to be moving toward a hard close after passing the revised Imperial House Law and clarifying its position on the Bank of Japan in the economic blueprint. Now, Takaichi must keep the ruling coalition together for another week while opposition parties look for new openings to challenge her over fiscal policy, inflation, the BOJ, imperial succession and Diet management.

The most immediate coalition issue is the secondary-capital bill. The proposal, strongly promoted by the Japan Innovation Party, cleared the House of Representatives before the extension but still needs upper house deliberation. For Ishin, the bill is not just another administrative reform measure. It is central to the party’s long-running argument that Japan needs to reduce excessive concentration in Tokyo and build a backup political and economic center.

For Takaichi’s Liberal Democratic Party, passing the bill would help stabilize coalition relations after the ruling bloc gave up on passing Lower House seat-reduction legislation during the current session. Ishin had treated seat reduction as one of its key reform priorities, and the delay left the coalition needing another visible achievement to prevent frustration from growing.

That makes the extended session a test of coalition management. Takaichi has already secured a conservative policy victory through the revised Imperial House Law, but she now needs to show Ishin that the coalition can also deliver on institutional reform and decentralization. Failure to make progress on the secondary-capital bill could deepen the sense that the LDP is using Ishin for numbers while prioritizing its own conservative agenda.

The revised Imperial House Law remains politically sensitive even after its passage on July 17. The law allows female imperial family members to remain in the Imperial House after marriage and permits the adoption of male descendants from former imperial branches. It also preserves the male-line succession system and does not allow female emperors.